Research ArticleExperimental Study on the Temperature Field of Cold RegionTunnel under Various Groundwater Seepage Velocities

Shiding Cao 1 Taishan Lu 23 Bo Zheng 4 and Guozhu Zhang 23

1Shenzhen Transportation Design amp Research Institute Co Ltd Shenzhen 518000 China2Institute of Geotechnical Engineering Southeast University Nanjing 210096 China3Jiangsu Key Laboratory of Urban Underground Engineering amp Environmental Safety Southeast UniversityNanjing 210096 China4Southwest Research Institute Co Ltd of C R E C Chengdu Sichuan 611731 China

Correspondence should be addressed to Taishan Lu 230189653seueducn

Received 16 October 2020 Revised 14 November 2020 Accepted 2 December 2020 Published 11 December 2020

Academic Editor Zhi Cheng Tang

Copyright copy 2020 Shiding Cao et al -is is an open access article distributed under the Creative Commons Attribution Licensewhich permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited

Groundwater seepage significantly affects the temperature field of a cold region tunnel Laboratory model tests are carried out toevaluate its effects yielding four main results First groundwater seepage can increase tunnel air temperature and decrease thethickness and length of the tunnel insulation layer Second groundwater seepage and tunnel ventilation exert a coupling effect onthe surrounding rock temperature -is effect is related to the surrounding rock depth -ird the influence of the groundwaterseepage velocity on the temperature of the interface between the lining and surrounding rock demonstrates a spatial differenceand the groundwater seepage leads to an uneven temperature distribution at the interface between the lining and surroundingrock Furthermore under groundwater seepage the shape and size of the tunnel cross section have significant effects on theinterface temperature Fourth the cold region tunnel has an antifreezing capability that is mainly related to the frost heaving of thesurrounding rock and the groundwater seepage velocity -is capability should be fully utilized in the design of cold regiontunnels -e experimental data presented can be used to verify the reliability of the theoretical calculation model for tunneltemperatures in cold regions

1 Introduction

Half of the worldrsquos land area is covered by transient per-mafrost seasonal frozen soil or permafrost [1 2] Coldregion tunnels have been increasingly built in recent yearsbut freezing damage to such tunnels threatens their struc-tural and operational safety [3ndash6] Aiming to solve theproblem of freezing damage to cold region tunnels inves-tigations on their temperature field have increased Forexample Lai et al [7] used dimensionless parameters andperturbation methods to approximate the temperaturedistribution of the surrounding rock of cold region tunnelsZhang et al [8] proposed an analytical solution for heatconduction in tunnels considering both composite mediumand time-dependent boundary conditions Lai et al [9]derived the governing equations for the coupled problems of

seepage temperature and stress fields with consideration ofthe ice-water phase change Zhang et al [10ndash12] derived anelement calculation formula for the thermo-hydro couplingmodel to explore how different construction seasons initialtemperatures and thermal insulation thicknesses affect thetemperature field of cold region tunnels Tan et al [13ndash15]used the ldquothree-zonerdquo model to derive the governingequation for the temperature field of surrounding rock -eairflow inside the tunnel and the heat convection betweenthe air and lining were simulated using the k-s turbulencemodel and the wall function Li et al [16] established awater-thermal coupling mathematical model for permafrostto determine the optimal thickness of the tunnel insulationlayer Yan et al [17] performed a numerical investigation onthe influences of different ventilation velocities on the designparameters of the thermal insulation layer

HindawiAdvances in Civil EngineeringVolume 2020 Article ID 6695099 14 pageshttpsdoiorg10115520206695099

-e above theoretical studies demonstrate the com-plexity of tunnel heat transfer in cold regions Model testscan also be used to study the temperature field of the coldregion tunnel Feng et al [18] developed a cold regiontunnel model consisting of a refrigeration system a cir-culation system and a temperature control system with a1 25 geometric reduced scale to study the temperaturefield and frost heave force of cold region tunnels and thereliability of thermal insulation layers Zhang et al [19]investigated the effects of the heat released during con-struction and of boundary temperatures on the temper-ature field of surrounding rock in permafrost tunnelsusing a model experiment with a 1 2683 geometric re-duced scale Speeding up construction and installinginsulation layers effectively weakened the negative effectsof thermal disturbance during construction and ofboundary temperatures Zeng et al [20] explored theinfluences of inlet airflow temperatures and mechanicalventilation on the temperature distribution of sur-rounding rock via a model test with a 1 30 geometricreduced scale under ventilation conditions -ey foundthat mechanical ventilation in the positive ventilationdirection adversely affects the freezing damage to coldregion tunnels Liu et al [21] built a tunnel model with a1 37 geometric reduced scale to explore the distributionof the temperature field and the expansion law of frostfront under different inlet airflow temperatures and windspeeds

Groundwater seepage has significant effects on thetemperature field of the surrounding rock in cold regiontunnels [9 13 22ndash24] -e frozen depth of cold regiontunnels is significantly affected by the seepage velocity [9]However the above model tests did not consider its effectson the temperature field of cold region tunnels In this paperheat transfer model tests of cold region tunnels experiencinggroundwater seepage are carried out -e model test resultsare used to analyze the distribution characteristics of thetemperature field and to reveal the gradual freezing processof cold region tunnels under groundwater seepage -eresults are also used to analyze the causes of freezing damageto cold region tunnels and to thereby provide a basis for itsprevention and control

2 Model Test

21 Investigating the Freezing Damage to a Prototype Tunnel-e freezing damage (shown in Figure 1) to two highwaytunnels one in the InnerMongolia Autonomous Region andthe other in Hebei Province is investigated

-e highway tunnel from the Inner Mongolia Auton-omous Region is a separated tunnel that is 3960m long onthe left and 3915m long on the right and the width of eachtunnel is 12m -e average wind speed is 12ms and themean annual temperature is minus26degC -e yearly frost-freeperiod lasts for approximately 95 days -e frost penetrationdepth is 3m -e tunnel was opened to traffic in November2012 In January 2013 the average temperature in was belowminus25degC and a large number of leakages and extensive road iceoccurred in the tunnel

-e highway tunnel from Hebei Province is a sepa-rated tunnel that is 2946m long on the left and 2992mlong on the right and the width of each tunnel is 12m-eaverage wind speed is 24ms and the mean annualtemperature is 32degC -e yearly frost-free period lasts forapproximately 120 days -e frost penetration depths ofthe entrance and exit of the tunnel are 14 m and 2mrespectively In January 2016 the tunnel experiencedextreme cold weather -e average temperature in January2016 was close to minus25degC Freezing damage such as leakageand water freezing occurred in the tunnel

Based on the freezing damage to two highway tunnels inthe Inner Mongolia Autonomous Region and Hebei Prov-ince a model test is conducted to investigate the distributionof the tunnel temperature field and the mechanism offreezing damage under various groundwater seepagevelocities

22 Similarity Criteria for the Prototype and Model Tunnels-e transient heat transfer in the concrete lining and sur-rounding rock of the tunnel prototype is governed byFourierrsquos law in the polar coordinates [25] as shown in thefollowing equation

zTp

ztp

αp

z2Tp

zr2p

+1rp

zTp

zrp

⎛⎝ ⎞⎠ rp gt ξp (1)

where subscript p indicates the tunnel prototype T is thetemperature r is the distance from the center of the tunnel tis the time α is the thermal diffusivity and ξ is the innerradius of the tunnel lining

-e transient heat transfer in the concrete lining andsurrounding rock of the tunnel model is governed byFourierrsquos law in the polar coordinates as shown in thefollowing equation

zTm

ztm

αm

z2Tm

zr2m

+1

rm

zTm

zrm

1113888 1113889 rm gt ξm (2)

where subscript m indicates the tunnel modelAccording to similarity theory [18 21] the heat transfer

similarity criteria can be defined as follows

π1 αt

r2

π2 Q

TC

(3)

where π1 and π2 are the heat transfer similarity criteria Q isthe latent heat of the phase change due to groundwaterfreezing and C is determined as follows

c αλ

(4)

Based on equation (3) the following similarity rela-tionships of temperature and time can be obtained

2 Advances in Civil Engineering

Tp

Tm

Qp

Qm

Cm

Cp

tp

tm

αm

αp

r2p

r2m

(5)

-e groundwater seepage in the rock surrounding thetunnel can be modeled as a homogeneous flow in a mediumwith an effective porosity [26] -e groundwater seepagevelocities of the tunnel prototype and tunnel model can beobtained using Darcyrsquos law as shown in the followingequation respectively

]p minusKp

zup

zrp

]m minusKm

zum

zrm

(6)

where ] is the groundwater seepage velocity u is the waterhead and K is the hydraulic conductivity

-ewater head of the tunnel model is the same as that of thetunnel prototype Based on equation (6) the following similarityrelationship for groundwater seepage velocity can be obtained

]p

]m

Kp

Km

rm

rp

(7)

Considering the research results of previous tunnel heattransfer model tests [16 18ndash21] and previous test conditions[22 23] a geometric similarity ratio of 1 30 between the tunnelmodel and tunnel prototype is selected According to equations(5) and (7) similarity ratios of 1 1 1 900 and 30 1 fortemperature time and velocity respectively are obtained

23 Model Test Design Figure 2 describes the design of thecold region tunnel model test under the conditions oftunnel ventilation and groundwater seepage In the modeltest the fractured rock mass is considered to be a ho-mogeneous medium with an effective porosity [26] thegroundwater seepage in the tunnel surrounding rock ismodeled as a homogeneous flow in a homogeneous me-dium with an effective porosity and the sand soil is used tosimulate the tunnel surrounding rock Constant water headtests are used to simulate the groundwater seepage field ofthe tunnel surrounding rock and water with a constantinlet temperature is used to simulate the undergroundtemperature field All of the tests have the same inlettemperature which is 13degC To ensure a uniform ground-water seepage field groundwater seepage occurs frombottom to top -e groundwater seepage velocity is con-trolled by adjusting the water head difference Cold airflowis blown into the tunnel through the closed circulationventilation ducts to freeze the groundwater in the tunnelsurrounding rock and the wind speed variation is con-trolled by changing the voltage applied to the air blower-e temperatures of the surrounding rock tunnel liningand air in the tunnel are measured by temperature sensors-e wind speed is measured by using an ultrasonic ane-mometer and the groundwater seepage velocity is mea-sured by using a liquid mass flow meter

24 Model Test Apparatus and Materials Figure 3 presentsthe apparatus of the laboratory model test which consists ofthe tunnel model box the tunnel ventilation system thegroundwater seepage system and the measuring system

Table 1 summarizes the model test equipment anddevices

Leakage

Freezing

Freezing

(a)

Leakage

Freezing

Freezing

(b)

Figure 1 Freezing damage to tunnels in (a) the Inner Mongolia Autonomous Region and (b) Hebei Province

Advances in Civil Engineering 3

Data logger

Return pipe

Geotextile

Pump

40

60

Temperature sensorUltrasonic anemometer

4 5TS9

TS3

TS1TL4

TS5

30

TA

37

40

TS7TS8

TS6

20183

TS4

TS2TS10TS11

Plastic permeableboard

Constanttemperature

tank

Insulationlayer

Water supply pipe

Thermal insulationtank

Liftingplatform

Flow meter

(a)

Thermal insulation pipe

Air blower

TA

TS8

TS3

120

TS7 37

4040

TS1

Refrigerator

Thermal insulationbox

Temperature sensorUltrasonic anemometer

(b)

Figure 2 Model test design (a) cross section and (b) vertical section

4 Advances in Civil Engineering

241 Tunnel Model -e tunnel model consists of a14mtimes 12mtimes 12m stainless steel box and a 18m concretetube with an outer diameter of 40 cm and a thickness of 2 cm-e concrete tube which has a circular cross section is made ofcement sand gravel and water in a ratio of 1 24 36 065Sand is used in the test -e sand-raining method is used to fillthe tunnel model with sand from the Yangtze River the densityand thermal conductivities of which are 205 gcm3 and158W(mmiddotdegC) respectively To minimize the heat transferboundary effect a 5-cm thick thermal insulation layer is in-stalled around the outer surface of the stainless steel box -eplastic permeable boards are installed at the top and bottom ofthe stainless steel box to ensure that the groundwater seepagespreads over the surrounding rock -e permeable plasticboards are wrapped with geotextile to prevent the groundwaterseepage from carrying away the sand

242 Tunnel Ventilation System -e ventilation systemconsists of a refrigerator an air blower a thermal insulationbox and a thermal insulation pipe-e thermal insulation pipeconnects the air blower the thermal insulation box and theconcrete tube to form closed circulation ventilation ducts -eair blower is installed on the top of the thermal insulation boxand the refrigerator is installed in the thermal insulation box-e air inside the refrigerator can be cooled to minus30degC and theairflow velocity in the ducts can reach 4ms

243 Groundwater Seepage System -e groundwaterseepage system consists of a constant temperature watertank a pump two thermal insulation water tanks two liftingplatforms a water supply pipe and a return pipe -e watersupply pipe and return pipe connect the constant temper-ature water tank the pump the thermal insulation watertanks and the stainless steel box to form a closed circulationsystem Both thermal insulation water tanks are placed onthe lifting platforms -e groundwater seepage velocity iscontrolled by adjusting the height difference between thetwo thermal insulation water tanks

244 Measuring System To monitor the temperature var-iations in the air surrounding rock and the interface be-tween the tunnel lining and surrounding rock a temperaturemonitoring cross section is installed in the middle of themodel box -e platinum resistance temperature sensor TAis installed in the center of the concrete tube to monitor thetemperature of the airflow -e platinum resistance tem-perature sensors TS7 to TS11 are installed in the sand tomonitor the temperature variation of the surrounding rocktemperature field at different positions and depths -eplatinum resistance temperature sensors TS1 to TS6 areinstalled on the concrete tube surface equally spaced alongthe cross section to monitor the temperature variation of theinterface between the tunnel lining and surrounding rock

Water tank

Tunnelmodel box

Data logger

Thermalinsulation pipe

Thermalinsulation

box

Refrigerator

Figure 3 Model test setup

Table 1 Model test equipment and devices

Item SpecificationConstant temperature tank Heating power is 6 kW volume is 1000 LPump Water head is 9m flow velocity is 30 Lmin-ermal insulation tank Volume is 18 LAir blower Maximum wind speed is 4msTemperature sensor Resistance temperature detector (HSRTD-3-100-A) with an accuracy of plusmn 015degCFlow meter Liquid mass flow meter (DMF-1-1-A) with a precision of plusmn 02 measurement scope is 0ndash40 kghUltrasonic anemometer Measurement scope is 0ndash40ms accuracy is 001msRefrigerator Refrigerating power is 2 kW minimum temperature is minus30degC

Advances in Civil Engineering 5

-e wind speed is monitored using an ultrasonic ane-mometer that is placed at the tunnel exit Finally the liquidmass flow meter is connected to the water return pipe of thegroundwater seepage system

25 Model Test Strategy Two factors are considered in themodel test namely wind speed and groundwater seepagevelocity Zhang et al [22] presented a systematic study of theheat transfer in tunnels under groundwater seepageGroundwater seepage velocities of less than 0864md hadnegligible effects on the temperature field of the surroundingrock -us groundwater seepage velocities of 0 0923 and2743md are chosen for this model-e average wind speedof the tunnel in the Inner Mongolia Autonomous Regionand in Hebei Province is 22ms and 24ms respectively-us wind speeds of 0606 1002 and 2398ms are chosenfor this model Table 2 presents the model test strategy -eexperiment time of each test is different as groundwaterseepage can prevent the surrounding rock from freezingHence the time that the temperature of surrounding rockdown to 0degC varies with groundwater seepage velocities -eexperiment times of 115 23 and 325 h for groundwaterseepage velocities of 0 0923 and 2743md respectively arechosen for this model-ese experiment times can guaranteea part of the surrounding rock around the lining will freeze

3 Results and Discussion

31 Effect of Groundwater Seepage on the Tunnel AirTemperature Figure 4 presents the variations in tunnel airtemperature over time under the effects of groundwaterseepage and ventilation in the model test Specifically itshows that the air temperature in the tunnel decreasesFurthermore the air temperature reduction rate decreasesover time and the temperature curve fluctuates every 12 hdue to the deicing of the refrigeration equipment Figure 4also shows that groundwater seepage velocity and windspeed have significant influences on tunnel air temperatureFigure 5 presents the variations in tunnel air temperature forvarious groundwater seepage velocities at different windspeeds after cooling for 115 h In Figure 5 the air tem-perature in the tunnel increases almost linearly as thegroundwater seepage velocity increases Furthermore theeffect of groundwater seepage velocity on air temperature inthe tunnel is related to wind speed -e lowest air tem-perature in the tunnel is minus2255degC under a groundwaterseepage velocity of 0ms and a wind speed of 0606ms -ehighest air temperature in the tunnel is minus1458degC under agroundwater seepage velocity of 2743md and a wind speedof 2398ms -us the higher the groundwater seepagevelocity and wind speed are the higher the air temperature isin the tunnel

-e above analysis shows that groundwater seepage has asignificant effect on the air temperature in a tunnel -ehigher the groundwater seepage velocity is the higher the airtemperature is in the tunnel Low air temperature in a tunnelmay induce tunnel freezing damage -e thickness andlength of the tunnel insulation layer are determined by the

air temperature in the tunnel Specifically the lower the airtemperature is in the tunnel the thicker and longer thetunnel insulation layer needs to be to avoid freezing damageIt can be speculated that groundwater seepage has a sig-nificant influence on the thickness and length of the tunnelinsulation layer in cold regions causing it to thin and short-us the influence of groundwater seepage should beconsidered when designing the insulation layers of coldregion tunnels

32 Effect of Groundwater Seepage on the Surrounding RockTemperature Figure 6 presents the variations in the sur-rounding rock temperature over time under the influence ofgroundwater seepage and ventilation in the model testSpecifically it shows that the surrounding rock temperatureat TS9 TS10 and TS11 decreases -e cooling rates andamplitudes of the surrounding rock temperature differsignificantly between TS9 TS10 and TS11 -e cooling rate

Table 2 Model test strategy

Test no Groundwater seepage velocity (md) Wind speed (ms)1

00606

2 10023 23984

09230606

5 10026 23987

27430606

8 10029 2398

Deicing of refrigeratorDeicing of refrigerator Groundwater

seepage

TA 18cm

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

5 10 15 20 25 300Time (h)

ndash25

ndash20

ndash15

ndash10

ndash5

0

5

10

15

Tem

pera

ture

(degC)

Figure 4 Variations in the tunnel air temperature over time

6 Advances in Civil Engineering

and amplitude of the surrounding rock temperature arerelated to the depth of the tunnel surrounding rock thegroundwater seepage velocity and the wind speed -ecooling rate and amplitude of the surrounding rock tem-perature at the TS9 monitoring point are the largest andthose at the TS11 monitoring point are the smallest -usthe deeper the tunnel surrounding rock is the lower thecooling rate and amplitude of the tunnel surrounding rocktemperature are Lower groundwater seepage velocities andhigher wind speeds lead to greater cooling rates and am-plitudes of the surrounding rock temperature -e influenceof groundwater seepage and tunnel ventilation on thesurrounding rock temperature field is related to the depth ofthe surrounding rock -e increase in wind speed has astrong influence on the temperature field at TS9 and TS10but a weak influence on that at TS11 Figure 6 also shows thatthe wind speed has the most significant influence on thesurrounding rock temperature field when the groundwaterseepage velocity is 0923md but has the least significantinfluence on the surrounding rock temperature field whenthe groundwater seepage velocity is 0md -is can beexplained by the coupling effect of groundwater seepage andtunnel ventilation

Figure 7 presents the variations in the surrounding rocktemperature drops under groundwater seepage velocities atdifferent wind speeds after 115h of cooling It also shows thatthe temperature drops in the tunnel surrounding rock decreaseas the groundwater seepage velocity increases -e temperaturedrops differ at TS9 TS10 and TS11 under different windspeeds -e temperature drop at TS11 at different wind speedsdecreases linearly as the groundwater seepage velocity increasesAt wind speeds of 0606ms and 1002ms the temperaturedrops at TS9 and TS10 decrease linearly as the groundwaterseepage velocity increases At a wind speed of 2398ms andgroundwater seepage velocity under 0923md the temperaturedrops at TS9 and TS10 slowly decrease as the groundwater

seepage velocity increases At a wind speed of 2398ms andgroundwater seepage velocity over 0923md the temperaturedrops at TS9 and TS10 sharply decrease as the groundwaterseepage velocity increases

-e above analysis shows that groundwater seepage andtunnel ventilation have a coupling effect on the surroundingrock temperature Specifically higher groundwater seepagevelocities and lower wind speeds lead to higher surroundingrock temperatures -us the coupling influence ofgroundwater seepage and tunnel ventilation should beconsidered when designing the insulation layers of coldregion tunnels

33 Effect of Groundwater Seepage on the Temperature at theInterface between the Lining and Surrounding RockFigure 8 presents the temperature variation over time at theinterface between the lining and surrounding rock under theinfluence of groundwater seepage and ventilation in themodel test It shows that the interface temperatures of TS1TS3 TS4 TS5 and TS6 decrease over time when ground-water seepage and ventilation are considered in the modeltest Groundwater seepage has a significant effect on theinterface temperature -e effect is related to the location ofthe monitoring points -erefore the cooling rates andamplitudes of the interface temperature for TS1 TS3 TS4TS5 and TS6 differ significantly -e groundwater seepagehas the most significant effects on measuring points TS3 andTS4 and has the least significant effects on measuring pointsTS1 and TS6 Wind speed also has a significant effect on theinterface temperature -e effect is related to the ground-water seepage velocity -ese results indicate that ground-water seepage and tunnel ventilation have a coupling effecton the interface temperature and that this coupling effect isrelated to the interface location

Figure 9 shows the variations in the temperature drops atTS1 TS3 TS4 TS5 and TS6 with groundwater seepagevelocity under tunnel ventilation after 115 h of cooling Itshows that the temperature drops at TS3 and TS4 upstreamof the groundwater seepage field decrease as the ground-water seepage velocity increases However the temperaturedrops at TS1 and TS6 downstream of the groundwaterseepage field increase as the groundwater seepage velocityincreases from 0 to 0923md Furthermore the temperaturedrops at TS1 and TS6 decrease as the groundwater seepagevelocity increases from 0923 to 2743md -e smallesttemperature drop occurs at TS3 (upstream of the ground-water seepage field) and the largest temperature drop occursat TS1 (downstream of the groundwater seepage field) undergroundwater seepage -ese results indicate that ground-water seepage leads to an uneven temperature distribution atthe interface between the lining and surrounding rock andthat tunnel ventilation enhances this uneven distribution

Figure 10 presents the temperature differences betweenTS3TS5 and TS6 -e temperature at TS3 is higher undergroundwater seepage than those at TS5 and TS6 -e interfacetemperature upstream of the groundwater field is higher thanthat downstream Figure 10 also shows that the temperaturedifference between TS3 and TS6 increases as the groundwater

Wind speed = 0606msWind speed = 1002msWind speed = 2389ms

Groundwater seepage

TA 18cm

ndash22

ndash21

ndash20

ndash19

ndash18

ndash17

ndash16

ndash15

Tem

pera

ture

(degC)

05 10 15 20 25 3000Groundwater seepage velocity (md)

Figure 5 Variations in the tunnel air temperature after 115 h ofcooling

Advances in Civil Engineering 7

Deicing of refrigerator Deicing of refrigerator

0 5 10 15 20 25 30Time (h)

0

2

4

6

8

10

12

14Te

mpe

ratu

re (deg

C)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(a)

Deicing of refrigeratorDeicing of refrigerator

0

2

4

6

8

10

12

14

Tem

pera

ture

(degC)

5 10 15 20 25 300Time (h)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(b)

Deicing of refrigerator

Groundwater seepage

TA TS9

1cm4cm 5cm

TS10 TS1118cm

Deicing of refrigerator

0

2

4

6

8

10

12

Tem

pera

ture

(degC)

5 10 15 20 25 300Time (h)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(c)

Figure 6 Variations in the surrounding rock temperature over time

8 Advances in Civil Engineering

seepage velocity increases -us the higher the groundwaterseepage velocity is the higher the temperature difference isbetween TS3 and TS6-e temperature difference between TS3and TS5 increases as the groundwater seepage velocity increasesfrom 0 to 0923md and decreases as the groundwater seepagevelocity increases from 0923 to 2743md Groundwaterseepage has a great effect on the interface temperature -iseffect has a spatial difference -us both the shape and size ofthe cross section of the tunnel significantly affect the interfacetemperature under groundwater seepage

34 Effect of Groundwater Seepage on the Freezing Damage toCold Region Tunnels -e tunnel drainage system is lo-cated between the lining and the surrounding rock

Monitoring points TS3 TS5 and TS6 are located at thetop middle and foot of the tunnel drainage systemrespectively -e temperatures at TS3 TS5 and TS6determine the antifreezing ability of cold region tunnels-erefore the higher the temperatures at TS3 TS5 andTS6 are the stronger the antifreezing capability of thetunnel in cold regions is Figure 8 shows that when thegroundwater seepage velocity is 0 md the measuringpoints TS3 TS5 and TS6 freeze synchronously If thetunnel surrounding rock is free of frost heaving coldregion tunnels may not need a thermal insulation layerWhen the groundwater seepage velocity is 0923 md themonitoring point TS6 freezes first -e interface thengradually freezes from TS6 to TS5 along the circumfer-ential direction of the tunnel section -is explains why

Tem

pera

ture

dro

p (deg

C)

Groundwater seepage

TS9TS10TS11

0

2

4

6

8

10

12

05 10 15 20 25 3000

18cm TA TS9 TS104cm

1cm5cm

TS11

Groundwater seepage velocity (md)

(a)

Tem

pera

ture

dro

p (deg

C)

TS9TS10TS11

Groundwater seepage

18cm TA TS9 TS104cm

1cm5cm

TS11

0

2

4

6

8

10

12

05 10 15 20 25 3000Groundwater seepage velocity (md)

(b)

Tem

pera

ture

dro

p (deg

C)

TS9TS10TS11

Groundwater seepage

18cm TA TS9 TS104cm

1cm5cm

TS11

0

2

4

6

8

10

12

05 10 15 20 25 3000Groundwater seepage velocity (md)

(c)

Figure 7 Variations in the surrounding rock temperature drop at different groundwater seepage velocities after 115 h of cooling Averagewind speed of (a) 0606ms (b) 1002ms and (c) 2398ms

Advances in Civil Engineering 9

ndash202468

101214

ndash202468

1012

Deicing of refrigeratorDeicing of refrigerator0degC

Deicing of refrigeratorDeicing of refrigerator

Deicing of refrigerator

0degC

Tem

pera

ture

(degC)

Tem

pera

ture

(degC)

ndash202468

101214

ndash202468

1012

Tem

pera

ture

(degC)

Tem

pera

ture

(degC)

Deicing of refrigerator Deicing of refrigerator

0degC 0degC

Deicing of refrigerator

0 5 10 15 20 25 30 0 5 10 15 20 25 30Time (h) Time (h)

0 5 10 15 20 25 30 0 5 10 15 20 25 30Time (h) Time (h)

(e)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(c) (d)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(a) (b)

ndash202468

1012

Tem

pera

ture

(degC)

ndash202468

1012

Tem

pera

ture

(degC)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Groundwater seepage

Deicing of refrigerator Deicing of refrigerator

0degC

0 5 10 15 20 25 30 0 5 10 15 20 25 30Time (h) Time (h)

TS1

TS6

TS5

TS4

TS3

18cmTA45deg

45deg

Figure 8 Variations in the temperature at the interface between the lining and the surrounding rock (a) TS1 (b) TS3 (c) TS4 (d) TS5 and(e) TS6

10 Advances in Civil Engineering

cold region tunnels suffer tunnel lining leakage and roadicing -e results of the model test reveal the cause oftunnel lining leakage and road icing To avoid tunnelleakage in cold region tunnels a thermal insulation layershould be properly designed and a heating device shouldbe installed in its longitudinal drainage pipe when thegroundwater seepage velocity is low When thegroundwater seepage velocity is 2743md the moni-toring point at TS6 freezes but the monitoring points atTS3 and TS5 do not Furthermore their temperatures do

not decrease significantly as cooling time increases-erefore the tunnel has good antifreezing capabilitywhen the groundwater seepage velocity is high -is goodantifreezing capability should be fully utilized Further-more the foot of the tunnel drainage system should bestrengthened against freezing via an insulation layer andheating device

-e above analysis demonstrates that cold region tunnelshave an antifreezing capability that is mainly related to the frostheaving of the surrounding rock and the groundwater seepage

Groundwater seepage

TS1TS3TS4

TS5TS6

Tem

pera

ture

dro

p (deg

C)

TA

TS3TS4

TS5

TS6TS1

45deg45deg

18cm

2

4

6

8

10

12

14

05 10 15 20 25 3000Groundwater seepage velocity (md)

(a)

TS1TS3TS4

TS5TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3TS4

TS5

TS6TS1

45deg45deg

18cm

2

4

6

8

10

12

14

05 10 15 20 25 3000Groundwater seepage velocity (md)

(b)

TS1TS3TS4

TS5TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3TS4

TS5

TS6TS1

45deg45deg

18cm

2

4

6

8

10

12

14

05 10 15 20 25 3000Groundwater seepage velocity (md)

(c)

Figure 9 Variations in the surrounding rock temperature drop at different groundwater seepage velocities after 115 h of cooling Averagewind speed of (a) 0606ms (b) 1002ms and (c) 2398ms

Advances in Civil Engineering 11

velocity -is antifreezing capability should be fully utilized inthe antifreezing design of cold region tunnels

4 Conclusions

A systematic study on the temperature field of cold regiontunnels is presented in which a model test that considers thecoupling effects of groundwater seepage and tunnel venti-lation is conducted -e effects of groundwater seepage onthe air temperature in the tunnel the surrounding rocktemperature the temperature at the interface between thelining and surrounding rock and the freezing damage of thetunnel in cold regions are studied -e following four mainconclusions are drawn

First groundwater seepage has a significant effect on theair temperature in the tunnel -e higher the groundwater

seepage velocity the higher the air temperature in thetunnel Groundwater seepage has a significant influence onthe thickness and length of the tunnel insulation layer in coldregions -e thickness and length of the tunnel insulationlayer can decrease under groundwater seepage

Second groundwater seepage and tunnel ventilationhave a coupling effect on the surrounding rock temperatureHigher groundwater seepage velocity and lower wind speedlead to higher surrounding rock temperature -e influenceof groundwater seepage and tunnel ventilation on thesurrounding rock temperature field is related to the depth ofthe surrounding rock

-ird groundwater seepage leads to an uneven tem-perature distribution at the interface between the lining andsurrounding rock -e tunnel ventilation further enhancesthis uneven temperature distribution -e groundwater

TS3-TS5TS3-TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3

TS5

TS6

45deg 18cm

ndash1

0

1

2

3

4

5

6

7

8

9

05 10 15 20 25 3000Groundwater seepage velocity (md)

(a)

TS3-TS5TS3-TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3

TS5

TS6

45deg 18cm

ndash1

0

1

2

3

4

5

6

7

8

9

05 10 15 20 25 3000Groundwater seepage velocity (md)

(b)

TS3-TS5TS3-TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3

TS5

TS6

45deg 18cm

ndash1

0

1

2

3

4

5

6

7

8

9

05 10 15 20 25 3000Groundwater seepage velocity (md)

(c)

Figure 10 Relationships between the temperature differences at TS5 TS6 and TS3 and groundwater seepage velocity Average wind speedof (a) 0606ms (b) 1002ms and (c) 2398ms

12 Advances in Civil Engineering

seepage and tunnel ventilation have a coupling effect on theinterface temperature -is coupling effect is related to theinterface location -e influence of the groundwater seepagevelocity on the interface temperature has a spatial difference-e shape and size of the cross section of the tunnel have asignificant influence on the interface temperature undergroundwater seepage

Fourth cold region tunnels have an antifreezing capa-bility that is mainly related to the frost heaving of thesurrounding rock and the groundwater seepage velocity-eantifreezing capability of the tunnel should be fully utilizedin the antifreezing design of cold region tunnels

Data Availability

-e data used to support the findings of this study areavailable from the corresponding author upon request

Conflicts of Interest

-e authors declare that they have no conflicts of interest

Acknowledgments

-is study was supported by the Key Laboratory of Geo-technical and Underground Engineering of Ministry ofEducation Tongji University (No KLE-TJGE-B1605) theKey Laboratory of Rock Mechanics and Geohazards ofZhejiang Province (No ZJRM-2018-Y-01) and the SichuanScience and Technology Program (No 2018GZ0359)

References

[1] S Li M Zhang W Pei and Y Lai ldquoExperimental and nu-merical simulations on heat-water-mechanics interactionmechanism in a freezing soilrdquo Applied =ermal Engineeringvol 132 pp 209ndash220 2018

[2] S Li M Zhang Y Tian W Pei and H Zhong ldquoExperimentaland numerical investigations on frost damage mechanism of acanal in cold regionsrdquo Cold Regions Science and Technologyvol 116 pp 1ndash11 2015

[3] S Shen C Xia J Huang and Y Li ldquoInfluence of seasonal meltlayer depth on the stability of surrounding rock in permafrostregions based on the measurementrdquoNatural Hazards vol 75no 3 pp 2545ndash2557 2015

[4] K-J Jun Y-C Hwang and C-Y Yune ldquoField measurementof temperature inside tunnel in winter in Gangwon KoreardquoCold Regions Science and Technology vol 143 pp 32ndash42 2017

[5] Q Ma X Luo Y Lai F Niu and J Gao ldquoNumerical in-vestigation on thermal insulation layer of a tunnel in sea-sonally frozen regionsrdquoApplied=ermal Engineering vol 138pp 280ndash291 2018

[6] X Zhao X Yang H Zhang H Lai and X Wang ldquoAnanalytical solution for frost heave force by the multifactor ofcoupled heat and moisture transfer in cold-region tunnelsrdquoCold Regions Science and Technology vol 175 2020

[7] Y M Lai S Y Liu Z W Wu and W Yu ldquoApproximateanalytical solution for temperature fields in cold regionscircular tunnelsrdquoCold Regions Science and Technology vol 34no 1 pp 43ndash49 2002

[8] G Zhang C Xia M Sun Y Zou and S Xiao ldquoA new modeland analytical solution for the heat conduction of tunnel

lining ground heat exchangersrdquo Cold Regions Science andTechnology vol 88 pp 59ndash66 2013

[9] Y M Lai Z W Wu Y L Zhu and L N Zhu ldquoNonlinearanalysis for the coupled problem of temperature seepage andstress fields in cold-region tunnelsrdquo Tunnelling and Under-ground Space Technology vol 13 no 4 pp 435ndash440 1998

[10] X Zhang J Xiao Y Zhang et al ldquoStudy of the function of theinsulation layer for treating water leakage in permafrosttunnelsrdquo Applied =ermal Engineering vol 27 no 2-3pp 637ndash645 2007

[11] X Zhang Y Lai W Yu and S Zhang ldquoNon-linear analysisfor the freezing-thawing situation of the rock surrounding thetunnel in cold regions under the conditions of differentconstruction seasons initial temperatures and insulationsrdquoTunnelling and Underground Space Technology vol 17 no 3pp 315ndash325 2002

[12] X Zhang Y Lai W Yu and Y Wu ldquoForecast analysis for there-frozen of Feng Huoshan permafrost tunnel on Qing-Zangrailwayrdquo Tunnelling and Underground Space Technologyvol 19 no 1 pp 45ndash56 2004

[13] X Tan W Chen H Tian and J Cao ldquoWater flow and heattransport including icewater phase change in porous medianumerical simulation and applicationrdquo Cold Regions Scienceand Technology vol 68 no 1-2 pp 74ndash84 2011

[14] X Tan W Chen G Wu and J Yang ldquoNumerical simulationsof heat transfer with ice-water phase change occurring inporous media and application to a cold-region tunnelrdquoTunnelling and Underground Space Technology vol 38pp 170ndash179 2013

[15] X Tan W Chen D Yang et al ldquoStudy on the influence ofairflow on the temperature of the surrounding rock in a coldregion tunnel and its application to insulation layer designrdquoApplied =ermal Engineering vol 67 no 1-2 pp 320ndash3342014

[16] S Li F Niu Y Lai W Pei and W Yu ldquoOptimal design ofthermal insulation layer of a tunnel in permafrost regionsbased on coupled heat-water simulationrdquo Applied =ermalEngineering vol 110 pp 1264ndash1273 2017

[17] Q Yan B Li Y Zhang J Yan and C Zhang ldquoNumericalinvestigation of heat-insulating layers in a cold region tunneltaking into account airflow and heat transferrdquo Applied Sci-ences vol 7 no 7 p 679 2017

[18] Q Feng B-S Jiang Q Zhang and G Wang ldquoReliabilityresearch on the 5-cm-thick insulation layer used in theYuximolegai tunnel based on a physical model testrdquo ColdRegions Science and Technology vol 124 pp 54ndash66 2016

[19] X Zhang Z Zhou J Li Y Zhou and F Han ldquoA physicalmodel experiment for investigating into temperature redis-tribution in surrounding rock of permafrost tunnelrdquo ColdRegions Science and Technology vol 151 pp 47ndash52 2018

[20] Y Zeng K Liu X Zhou and L Fan ldquoTunnel temperaturefields analysis under the couple effect of convection-con-duction in cold regionsrdquo Applied =ermal Engineeringvol 120 pp 378ndash392 2017

[21] L Liu Z Li X Liu and Y Li ldquoFrost front research of a cold-region tunnel considering ventilation based on a physicalmodel testrdquo Tunnelling and Underground Space Technologyvol 77 pp 261ndash279 2018

[22] G Zhang Y Guo Y Zhou et al ldquoExperimental study on thethermal performance of tunnel lining GHE under ground-water flowrdquo Applied =ermal Engineering vol 106 pp 784ndash795 2016

[23] G Zhang S Liu X Zhao et al ldquo-e coupling effect ofventilation and groundwater flow on the thermal performance

Advances in Civil Engineering 13

of tunnel lining GHEsrdquoApplied=ermal Engineering vol 112pp 595ndash605 2017

[24] Q Hu R Shi Y Hu et al ldquoMethod to evaluate the safety oftunnels through steeply inclined strata in cold regions basedon the sidewall frost heave modelrdquo Journal of Performance ofConstructed Facilities vol 32 2018

[25] H Cai P Li and Z Wu ldquoModel test of liquid nitrogenfreezing-temperature field of improved plastic freezing piperdquoJournal of Cold Regions Engineering vol 34 no 1 2020

[26] S E A Gehlin and G Hellstrom ldquoInfluence on thermalresponse test by groundwater flow in vertical fractures in hardrockrdquo Renewable Energy vol 28 no 14 pp 2221ndash2238 2003

14 Advances in Civil Engineering

Tp

Tm

Qp

Qm

Cm

Cp

tp

tm

αm

αp

r2p

r2m

(5)

-e groundwater seepage in the rock surrounding thetunnel can be modeled as a homogeneous flow in a mediumwith an effective porosity [26] -e groundwater seepagevelocities of the tunnel prototype and tunnel model can beobtained using Darcyrsquos law as shown in the followingequation respectively

]p minusKp

zup

zrp

]m minusKm

zum

zrm

(6)

where ] is the groundwater seepage velocity u is the waterhead and K is the hydraulic conductivity

-ewater head of the tunnel model is the same as that of thetunnel prototype Based on equation (6) the following similarityrelationship for groundwater seepage velocity can be obtained

]p

]m

Kp

Km

rm

rp

(7)

Considering the research results of previous tunnel heattransfer model tests [16 18ndash21] and previous test conditions[22 23] a geometric similarity ratio of 1 30 between the tunnelmodel and tunnel prototype is selected According to equations(5) and (7) similarity ratios of 1 1 1 900 and 30 1 fortemperature time and velocity respectively are obtained

23 Model Test Design Figure 2 describes the design of thecold region tunnel model test under the conditions oftunnel ventilation and groundwater seepage In the modeltest the fractured rock mass is considered to be a ho-mogeneous medium with an effective porosity [26] thegroundwater seepage in the tunnel surrounding rock ismodeled as a homogeneous flow in a homogeneous me-dium with an effective porosity and the sand soil is used tosimulate the tunnel surrounding rock Constant water headtests are used to simulate the groundwater seepage field ofthe tunnel surrounding rock and water with a constantinlet temperature is used to simulate the undergroundtemperature field All of the tests have the same inlettemperature which is 13degC To ensure a uniform ground-water seepage field groundwater seepage occurs frombottom to top -e groundwater seepage velocity is con-trolled by adjusting the water head difference Cold airflowis blown into the tunnel through the closed circulationventilation ducts to freeze the groundwater in the tunnelsurrounding rock and the wind speed variation is con-trolled by changing the voltage applied to the air blower-e temperatures of the surrounding rock tunnel liningand air in the tunnel are measured by temperature sensors-e wind speed is measured by using an ultrasonic ane-mometer and the groundwater seepage velocity is mea-sured by using a liquid mass flow meter

24 Model Test Apparatus and Materials Figure 3 presentsthe apparatus of the laboratory model test which consists ofthe tunnel model box the tunnel ventilation system thegroundwater seepage system and the measuring system

Table 1 summarizes the model test equipment anddevices

Leakage

Freezing

Freezing

(a)

Leakage

Freezing

Freezing

(b)

Figure 1 Freezing damage to tunnels in (a) the Inner Mongolia Autonomous Region and (b) Hebei Province

Advances in Civil Engineering 3

Data logger

Return pipe

Geotextile

Pump

40

60

Temperature sensorUltrasonic anemometer

4 5TS9

TS3

TS1TL4

TS5

30

TA

37

40

TS7TS8

TS6

20183

TS4

TS2TS10TS11

Plastic permeableboard

Constanttemperature

tank

Insulationlayer

Water supply pipe

Thermal insulationtank

Liftingplatform

Flow meter

(a)

Thermal insulation pipe

Air blower

TA

TS8

TS3

120

TS7 37

4040

TS1

Refrigerator

Thermal insulationbox

Temperature sensorUltrasonic anemometer

(b)

Figure 2 Model test design (a) cross section and (b) vertical section

4 Advances in Civil Engineering

241 Tunnel Model -e tunnel model consists of a14mtimes 12mtimes 12m stainless steel box and a 18m concretetube with an outer diameter of 40 cm and a thickness of 2 cm-e concrete tube which has a circular cross section is made ofcement sand gravel and water in a ratio of 1 24 36 065Sand is used in the test -e sand-raining method is used to fillthe tunnel model with sand from the Yangtze River the densityand thermal conductivities of which are 205 gcm3 and158W(mmiddotdegC) respectively To minimize the heat transferboundary effect a 5-cm thick thermal insulation layer is in-stalled around the outer surface of the stainless steel box -eplastic permeable boards are installed at the top and bottom ofthe stainless steel box to ensure that the groundwater seepagespreads over the surrounding rock -e permeable plasticboards are wrapped with geotextile to prevent the groundwaterseepage from carrying away the sand

242 Tunnel Ventilation System -e ventilation systemconsists of a refrigerator an air blower a thermal insulationbox and a thermal insulation pipe-e thermal insulation pipeconnects the air blower the thermal insulation box and theconcrete tube to form closed circulation ventilation ducts -eair blower is installed on the top of the thermal insulation boxand the refrigerator is installed in the thermal insulation box-e air inside the refrigerator can be cooled to minus30degC and theairflow velocity in the ducts can reach 4ms

243 Groundwater Seepage System -e groundwaterseepage system consists of a constant temperature watertank a pump two thermal insulation water tanks two liftingplatforms a water supply pipe and a return pipe -e watersupply pipe and return pipe connect the constant temper-ature water tank the pump the thermal insulation watertanks and the stainless steel box to form a closed circulationsystem Both thermal insulation water tanks are placed onthe lifting platforms -e groundwater seepage velocity iscontrolled by adjusting the height difference between thetwo thermal insulation water tanks

244 Measuring System To monitor the temperature var-iations in the air surrounding rock and the interface be-tween the tunnel lining and surrounding rock a temperaturemonitoring cross section is installed in the middle of themodel box -e platinum resistance temperature sensor TAis installed in the center of the concrete tube to monitor thetemperature of the airflow -e platinum resistance tem-perature sensors TS7 to TS11 are installed in the sand tomonitor the temperature variation of the surrounding rocktemperature field at different positions and depths -eplatinum resistance temperature sensors TS1 to TS6 areinstalled on the concrete tube surface equally spaced alongthe cross section to monitor the temperature variation of theinterface between the tunnel lining and surrounding rock

Water tank

Tunnelmodel box

Data logger

Thermalinsulation pipe

Thermalinsulation

box

Refrigerator

Figure 3 Model test setup

Table 1 Model test equipment and devices

Item SpecificationConstant temperature tank Heating power is 6 kW volume is 1000 LPump Water head is 9m flow velocity is 30 Lmin-ermal insulation tank Volume is 18 LAir blower Maximum wind speed is 4msTemperature sensor Resistance temperature detector (HSRTD-3-100-A) with an accuracy of plusmn 015degCFlow meter Liquid mass flow meter (DMF-1-1-A) with a precision of plusmn 02 measurement scope is 0ndash40 kghUltrasonic anemometer Measurement scope is 0ndash40ms accuracy is 001msRefrigerator Refrigerating power is 2 kW minimum temperature is minus30degC

Advances in Civil Engineering 5

-e wind speed is monitored using an ultrasonic ane-mometer that is placed at the tunnel exit Finally the liquidmass flow meter is connected to the water return pipe of thegroundwater seepage system

25 Model Test Strategy Two factors are considered in themodel test namely wind speed and groundwater seepagevelocity Zhang et al [22] presented a systematic study of theheat transfer in tunnels under groundwater seepageGroundwater seepage velocities of less than 0864md hadnegligible effects on the temperature field of the surroundingrock -us groundwater seepage velocities of 0 0923 and2743md are chosen for this model-e average wind speedof the tunnel in the Inner Mongolia Autonomous Regionand in Hebei Province is 22ms and 24ms respectively-us wind speeds of 0606 1002 and 2398ms are chosenfor this model Table 2 presents the model test strategy -eexperiment time of each test is different as groundwaterseepage can prevent the surrounding rock from freezingHence the time that the temperature of surrounding rockdown to 0degC varies with groundwater seepage velocities -eexperiment times of 115 23 and 325 h for groundwaterseepage velocities of 0 0923 and 2743md respectively arechosen for this model-ese experiment times can guaranteea part of the surrounding rock around the lining will freeze

3 Results and Discussion

31 Effect of Groundwater Seepage on the Tunnel AirTemperature Figure 4 presents the variations in tunnel airtemperature over time under the effects of groundwaterseepage and ventilation in the model test Specifically itshows that the air temperature in the tunnel decreasesFurthermore the air temperature reduction rate decreasesover time and the temperature curve fluctuates every 12 hdue to the deicing of the refrigeration equipment Figure 4also shows that groundwater seepage velocity and windspeed have significant influences on tunnel air temperatureFigure 5 presents the variations in tunnel air temperature forvarious groundwater seepage velocities at different windspeeds after cooling for 115 h In Figure 5 the air tem-perature in the tunnel increases almost linearly as thegroundwater seepage velocity increases Furthermore theeffect of groundwater seepage velocity on air temperature inthe tunnel is related to wind speed -e lowest air tem-perature in the tunnel is minus2255degC under a groundwaterseepage velocity of 0ms and a wind speed of 0606ms -ehighest air temperature in the tunnel is minus1458degC under agroundwater seepage velocity of 2743md and a wind speedof 2398ms -us the higher the groundwater seepagevelocity and wind speed are the higher the air temperature isin the tunnel

-e above analysis shows that groundwater seepage has asignificant effect on the air temperature in a tunnel -ehigher the groundwater seepage velocity is the higher the airtemperature is in the tunnel Low air temperature in a tunnelmay induce tunnel freezing damage -e thickness andlength of the tunnel insulation layer are determined by the

air temperature in the tunnel Specifically the lower the airtemperature is in the tunnel the thicker and longer thetunnel insulation layer needs to be to avoid freezing damageIt can be speculated that groundwater seepage has a sig-nificant influence on the thickness and length of the tunnelinsulation layer in cold regions causing it to thin and short-us the influence of groundwater seepage should beconsidered when designing the insulation layers of coldregion tunnels

32 Effect of Groundwater Seepage on the Surrounding RockTemperature Figure 6 presents the variations in the sur-rounding rock temperature over time under the influence ofgroundwater seepage and ventilation in the model testSpecifically it shows that the surrounding rock temperatureat TS9 TS10 and TS11 decreases -e cooling rates andamplitudes of the surrounding rock temperature differsignificantly between TS9 TS10 and TS11 -e cooling rate

Table 2 Model test strategy

Test no Groundwater seepage velocity (md) Wind speed (ms)1

00606

2 10023 23984

09230606

5 10026 23987

27430606

8 10029 2398

Deicing of refrigeratorDeicing of refrigerator Groundwater

seepage

TA 18cm

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

5 10 15 20 25 300Time (h)

ndash25

ndash20

ndash15

ndash10

ndash5

0

5

10

15

Tem

pera

ture

(degC)

Figure 4 Variations in the tunnel air temperature over time

6 Advances in Civil Engineering

and amplitude of the surrounding rock temperature arerelated to the depth of the tunnel surrounding rock thegroundwater seepage velocity and the wind speed -ecooling rate and amplitude of the surrounding rock tem-perature at the TS9 monitoring point are the largest andthose at the TS11 monitoring point are the smallest -usthe deeper the tunnel surrounding rock is the lower thecooling rate and amplitude of the tunnel surrounding rocktemperature are Lower groundwater seepage velocities andhigher wind speeds lead to greater cooling rates and am-plitudes of the surrounding rock temperature -e influenceof groundwater seepage and tunnel ventilation on thesurrounding rock temperature field is related to the depth ofthe surrounding rock -e increase in wind speed has astrong influence on the temperature field at TS9 and TS10but a weak influence on that at TS11 Figure 6 also shows thatthe wind speed has the most significant influence on thesurrounding rock temperature field when the groundwaterseepage velocity is 0923md but has the least significantinfluence on the surrounding rock temperature field whenthe groundwater seepage velocity is 0md -is can beexplained by the coupling effect of groundwater seepage andtunnel ventilation

Figure 7 presents the variations in the surrounding rocktemperature drops under groundwater seepage velocities atdifferent wind speeds after 115h of cooling It also shows thatthe temperature drops in the tunnel surrounding rock decreaseas the groundwater seepage velocity increases -e temperaturedrops differ at TS9 TS10 and TS11 under different windspeeds -e temperature drop at TS11 at different wind speedsdecreases linearly as the groundwater seepage velocity increasesAt wind speeds of 0606ms and 1002ms the temperaturedrops at TS9 and TS10 decrease linearly as the groundwaterseepage velocity increases At a wind speed of 2398ms andgroundwater seepage velocity under 0923md the temperaturedrops at TS9 and TS10 slowly decrease as the groundwater

seepage velocity increases At a wind speed of 2398ms andgroundwater seepage velocity over 0923md the temperaturedrops at TS9 and TS10 sharply decrease as the groundwaterseepage velocity increases

-e above analysis shows that groundwater seepage andtunnel ventilation have a coupling effect on the surroundingrock temperature Specifically higher groundwater seepagevelocities and lower wind speeds lead to higher surroundingrock temperatures -us the coupling influence ofgroundwater seepage and tunnel ventilation should beconsidered when designing the insulation layers of coldregion tunnels

33 Effect of Groundwater Seepage on the Temperature at theInterface between the Lining and Surrounding RockFigure 8 presents the temperature variation over time at theinterface between the lining and surrounding rock under theinfluence of groundwater seepage and ventilation in themodel test It shows that the interface temperatures of TS1TS3 TS4 TS5 and TS6 decrease over time when ground-water seepage and ventilation are considered in the modeltest Groundwater seepage has a significant effect on theinterface temperature -e effect is related to the location ofthe monitoring points -erefore the cooling rates andamplitudes of the interface temperature for TS1 TS3 TS4TS5 and TS6 differ significantly -e groundwater seepagehas the most significant effects on measuring points TS3 andTS4 and has the least significant effects on measuring pointsTS1 and TS6 Wind speed also has a significant effect on theinterface temperature -e effect is related to the ground-water seepage velocity -ese results indicate that ground-water seepage and tunnel ventilation have a coupling effecton the interface temperature and that this coupling effect isrelated to the interface location

Figure 9 shows the variations in the temperature drops atTS1 TS3 TS4 TS5 and TS6 with groundwater seepagevelocity under tunnel ventilation after 115 h of cooling Itshows that the temperature drops at TS3 and TS4 upstreamof the groundwater seepage field decrease as the ground-water seepage velocity increases However the temperaturedrops at TS1 and TS6 downstream of the groundwaterseepage field increase as the groundwater seepage velocityincreases from 0 to 0923md Furthermore the temperaturedrops at TS1 and TS6 decrease as the groundwater seepagevelocity increases from 0923 to 2743md -e smallesttemperature drop occurs at TS3 (upstream of the ground-water seepage field) and the largest temperature drop occursat TS1 (downstream of the groundwater seepage field) undergroundwater seepage -ese results indicate that ground-water seepage leads to an uneven temperature distribution atthe interface between the lining and surrounding rock andthat tunnel ventilation enhances this uneven distribution

Figure 10 presents the temperature differences betweenTS3TS5 and TS6 -e temperature at TS3 is higher undergroundwater seepage than those at TS5 and TS6 -e interfacetemperature upstream of the groundwater field is higher thanthat downstream Figure 10 also shows that the temperaturedifference between TS3 and TS6 increases as the groundwater

Wind speed = 0606msWind speed = 1002msWind speed = 2389ms

Groundwater seepage

TA 18cm

ndash22

ndash21

ndash20

ndash19

ndash18

ndash17

ndash16

ndash15

Tem

pera

ture

(degC)

05 10 15 20 25 3000Groundwater seepage velocity (md)

Figure 5 Variations in the tunnel air temperature after 115 h ofcooling

Advances in Civil Engineering 7

Deicing of refrigerator Deicing of refrigerator

0 5 10 15 20 25 30Time (h)

0

2

4

6

8

10

12

14Te

mpe

ratu

re (deg

C)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(a)

Deicing of refrigeratorDeicing of refrigerator

0

2

4

6

8

10

12

14

Tem

pera

ture

(degC)

5 10 15 20 25 300Time (h)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(b)

Deicing of refrigerator

Groundwater seepage

TA TS9

1cm4cm 5cm

TS10 TS1118cm

Deicing of refrigerator

0

2

4

6

8

10

12

Tem

pera

ture

(degC)

5 10 15 20 25 300Time (h)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(c)

Figure 6 Variations in the surrounding rock temperature over time

8 Advances in Civil Engineering

seepage velocity increases -us the higher the groundwaterseepage velocity is the higher the temperature difference isbetween TS3 and TS6-e temperature difference between TS3and TS5 increases as the groundwater seepage velocity increasesfrom 0 to 0923md and decreases as the groundwater seepagevelocity increases from 0923 to 2743md Groundwaterseepage has a great effect on the interface temperature -iseffect has a spatial difference -us both the shape and size ofthe cross section of the tunnel significantly affect the interfacetemperature under groundwater seepage

34 Effect of Groundwater Seepage on the Freezing Damage toCold Region Tunnels -e tunnel drainage system is lo-cated between the lining and the surrounding rock

Monitoring points TS3 TS5 and TS6 are located at thetop middle and foot of the tunnel drainage systemrespectively -e temperatures at TS3 TS5 and TS6determine the antifreezing ability of cold region tunnels-erefore the higher the temperatures at TS3 TS5 andTS6 are the stronger the antifreezing capability of thetunnel in cold regions is Figure 8 shows that when thegroundwater seepage velocity is 0 md the measuringpoints TS3 TS5 and TS6 freeze synchronously If thetunnel surrounding rock is free of frost heaving coldregion tunnels may not need a thermal insulation layerWhen the groundwater seepage velocity is 0923 md themonitoring point TS6 freezes first -e interface thengradually freezes from TS6 to TS5 along the circumfer-ential direction of the tunnel section -is explains why

Tem

pera

ture

dro

p (deg

C)

Groundwater seepage

TS9TS10TS11

0

2

4

6

8

10

12

05 10 15 20 25 3000

18cm TA TS9 TS104cm

1cm5cm

TS11

Groundwater seepage velocity (md)

(a)

Tem

pera

ture

dro

p (deg

C)

TS9TS10TS11

Groundwater seepage

18cm TA TS9 TS104cm

1cm5cm

TS11

0

2

4

6

8

10

12

05 10 15 20 25 3000Groundwater seepage velocity (md)

(b)

Tem

pera

ture

dro

p (deg

C)

TS9TS10TS11

Groundwater seepage

18cm TA TS9 TS104cm

1cm5cm

TS11

0

2

4

6

8

10

12

05 10 15 20 25 3000Groundwater seepage velocity (md)

(c)

Figure 7 Variations in the surrounding rock temperature drop at different groundwater seepage velocities after 115 h of cooling Averagewind speed of (a) 0606ms (b) 1002ms and (c) 2398ms

Advances in Civil Engineering 9

ndash202468

101214

ndash202468

1012

Deicing of refrigeratorDeicing of refrigerator0degC

Deicing of refrigeratorDeicing of refrigerator

Deicing of refrigerator

0degC

Tem

pera

ture

(degC)

Tem

pera

ture

(degC)

ndash202468

101214

ndash202468

1012

Tem

pera

ture

(degC)

Tem

pera

ture

(degC)

Deicing of refrigerator Deicing of refrigerator

0degC 0degC

Deicing of refrigerator

0 5 10 15 20 25 30 0 5 10 15 20 25 30Time (h) Time (h)

0 5 10 15 20 25 30 0 5 10 15 20 25 30Time (h) Time (h)

(e)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(c) (d)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(a) (b)

ndash202468

1012

Tem

pera

ture

(degC)

ndash202468

1012

Tem

pera

ture

(degC)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Groundwater seepage

Deicing of refrigerator Deicing of refrigerator

0degC

0 5 10 15 20 25 30 0 5 10 15 20 25 30Time (h) Time (h)

TS1

TS6

TS5

TS4

TS3

18cmTA45deg

45deg

Figure 8 Variations in the temperature at the interface between the lining and the surrounding rock (a) TS1 (b) TS3 (c) TS4 (d) TS5 and(e) TS6

10 Advances in Civil Engineering

cold region tunnels suffer tunnel lining leakage and roadicing -e results of the model test reveal the cause oftunnel lining leakage and road icing To avoid tunnelleakage in cold region tunnels a thermal insulation layershould be properly designed and a heating device shouldbe installed in its longitudinal drainage pipe when thegroundwater seepage velocity is low When thegroundwater seepage velocity is 2743md the moni-toring point at TS6 freezes but the monitoring points atTS3 and TS5 do not Furthermore their temperatures do

not decrease significantly as cooling time increases-erefore the tunnel has good antifreezing capabilitywhen the groundwater seepage velocity is high -is goodantifreezing capability should be fully utilized Further-more the foot of the tunnel drainage system should bestrengthened against freezing via an insulation layer andheating device

-e above analysis demonstrates that cold region tunnelshave an antifreezing capability that is mainly related to the frostheaving of the surrounding rock and the groundwater seepage

Groundwater seepage

TS1TS3TS4

TS5TS6

Tem

pera

ture

dro

p (deg

C)

TA

TS3TS4

TS5

TS6TS1

45deg45deg

18cm

2

4

6

8

10

12

14

05 10 15 20 25 3000Groundwater seepage velocity (md)

(a)

TS1TS3TS4

TS5TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3TS4

TS5

TS6TS1

45deg45deg

18cm

2

4

6

8

10

12

14

05 10 15 20 25 3000Groundwater seepage velocity (md)

(b)

TS1TS3TS4

TS5TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3TS4

TS5

TS6TS1

45deg45deg

18cm

2

4

6

8

10

12

14

05 10 15 20 25 3000Groundwater seepage velocity (md)

(c)

Figure 9 Variations in the surrounding rock temperature drop at different groundwater seepage velocities after 115 h of cooling Averagewind speed of (a) 0606ms (b) 1002ms and (c) 2398ms

Advances in Civil Engineering 11

velocity -is antifreezing capability should be fully utilized inthe antifreezing design of cold region tunnels

4 Conclusions

A systematic study on the temperature field of cold regiontunnels is presented in which a model test that considers thecoupling effects of groundwater seepage and tunnel venti-lation is conducted -e effects of groundwater seepage onthe air temperature in the tunnel the surrounding rocktemperature the temperature at the interface between thelining and surrounding rock and the freezing damage of thetunnel in cold regions are studied -e following four mainconclusions are drawn

First groundwater seepage has a significant effect on theair temperature in the tunnel -e higher the groundwater

seepage velocity the higher the air temperature in thetunnel Groundwater seepage has a significant influence onthe thickness and length of the tunnel insulation layer in coldregions -e thickness and length of the tunnel insulationlayer can decrease under groundwater seepage

Second groundwater seepage and tunnel ventilationhave a coupling effect on the surrounding rock temperatureHigher groundwater seepage velocity and lower wind speedlead to higher surrounding rock temperature -e influenceof groundwater seepage and tunnel ventilation on thesurrounding rock temperature field is related to the depth ofthe surrounding rock

-ird groundwater seepage leads to an uneven tem-perature distribution at the interface between the lining andsurrounding rock -e tunnel ventilation further enhancesthis uneven temperature distribution -e groundwater

TS3-TS5TS3-TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3

TS5

TS6

45deg 18cm

ndash1

0

1

2

3

4

5

6

7

8

9

05 10 15 20 25 3000Groundwater seepage velocity (md)

(a)

TS3-TS5TS3-TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3

TS5

TS6

45deg 18cm

ndash1

0

1

2

3

4

5

6

7

8

9

05 10 15 20 25 3000Groundwater seepage velocity (md)

(b)

TS3-TS5TS3-TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3

TS5

TS6

45deg 18cm

ndash1

0

1

2

3

4

5

6

7

8

9

05 10 15 20 25 3000Groundwater seepage velocity (md)

(c)

Figure 10 Relationships between the temperature differences at TS5 TS6 and TS3 and groundwater seepage velocity Average wind speedof (a) 0606ms (b) 1002ms and (c) 2398ms

12 Advances in Civil Engineering

seepage and tunnel ventilation have a coupling effect on theinterface temperature -is coupling effect is related to theinterface location -e influence of the groundwater seepagevelocity on the interface temperature has a spatial difference-e shape and size of the cross section of the tunnel have asignificant influence on the interface temperature undergroundwater seepage

Fourth cold region tunnels have an antifreezing capa-bility that is mainly related to the frost heaving of thesurrounding rock and the groundwater seepage velocity-eantifreezing capability of the tunnel should be fully utilizedin the antifreezing design of cold region tunnels

Data Availability

-e data used to support the findings of this study areavailable from the corresponding author upon request

Conflicts of Interest

-e authors declare that they have no conflicts of interest

Acknowledgments

-is study was supported by the Key Laboratory of Geo-technical and Underground Engineering of Ministry ofEducation Tongji University (No KLE-TJGE-B1605) theKey Laboratory of Rock Mechanics and Geohazards ofZhejiang Province (No ZJRM-2018-Y-01) and the SichuanScience and Technology Program (No 2018GZ0359)

References

[1] S Li M Zhang W Pei and Y Lai ldquoExperimental and nu-merical simulations on heat-water-mechanics interactionmechanism in a freezing soilrdquo Applied =ermal Engineeringvol 132 pp 209ndash220 2018

[2] S Li M Zhang Y Tian W Pei and H Zhong ldquoExperimentaland numerical investigations on frost damage mechanism of acanal in cold regionsrdquo Cold Regions Science and Technologyvol 116 pp 1ndash11 2015

[3] S Shen C Xia J Huang and Y Li ldquoInfluence of seasonal meltlayer depth on the stability of surrounding rock in permafrostregions based on the measurementrdquoNatural Hazards vol 75no 3 pp 2545ndash2557 2015

[4] K-J Jun Y-C Hwang and C-Y Yune ldquoField measurementof temperature inside tunnel in winter in Gangwon KoreardquoCold Regions Science and Technology vol 143 pp 32ndash42 2017

[5] Q Ma X Luo Y Lai F Niu and J Gao ldquoNumerical in-vestigation on thermal insulation layer of a tunnel in sea-sonally frozen regionsrdquoApplied=ermal Engineering vol 138pp 280ndash291 2018

[6] X Zhao X Yang H Zhang H Lai and X Wang ldquoAnanalytical solution for frost heave force by the multifactor ofcoupled heat and moisture transfer in cold-region tunnelsrdquoCold Regions Science and Technology vol 175 2020

[7] Y M Lai S Y Liu Z W Wu and W Yu ldquoApproximateanalytical solution for temperature fields in cold regionscircular tunnelsrdquoCold Regions Science and Technology vol 34no 1 pp 43ndash49 2002

[8] G Zhang C Xia M Sun Y Zou and S Xiao ldquoA new modeland analytical solution for the heat conduction of tunnel

lining ground heat exchangersrdquo Cold Regions Science andTechnology vol 88 pp 59ndash66 2013

[9] Y M Lai Z W Wu Y L Zhu and L N Zhu ldquoNonlinearanalysis for the coupled problem of temperature seepage andstress fields in cold-region tunnelsrdquo Tunnelling and Under-ground Space Technology vol 13 no 4 pp 435ndash440 1998

[10] X Zhang J Xiao Y Zhang et al ldquoStudy of the function of theinsulation layer for treating water leakage in permafrosttunnelsrdquo Applied =ermal Engineering vol 27 no 2-3pp 637ndash645 2007

[11] X Zhang Y Lai W Yu and S Zhang ldquoNon-linear analysisfor the freezing-thawing situation of the rock surrounding thetunnel in cold regions under the conditions of differentconstruction seasons initial temperatures and insulationsrdquoTunnelling and Underground Space Technology vol 17 no 3pp 315ndash325 2002

[12] X Zhang Y Lai W Yu and Y Wu ldquoForecast analysis for there-frozen of Feng Huoshan permafrost tunnel on Qing-Zangrailwayrdquo Tunnelling and Underground Space Technologyvol 19 no 1 pp 45ndash56 2004

[13] X Tan W Chen H Tian and J Cao ldquoWater flow and heattransport including icewater phase change in porous medianumerical simulation and applicationrdquo Cold Regions Scienceand Technology vol 68 no 1-2 pp 74ndash84 2011

[14] X Tan W Chen G Wu and J Yang ldquoNumerical simulationsof heat transfer with ice-water phase change occurring inporous media and application to a cold-region tunnelrdquoTunnelling and Underground Space Technology vol 38pp 170ndash179 2013

[15] X Tan W Chen D Yang et al ldquoStudy on the influence ofairflow on the temperature of the surrounding rock in a coldregion tunnel and its application to insulation layer designrdquoApplied =ermal Engineering vol 67 no 1-2 pp 320ndash3342014

[16] S Li F Niu Y Lai W Pei and W Yu ldquoOptimal design ofthermal insulation layer of a tunnel in permafrost regionsbased on coupled heat-water simulationrdquo Applied =ermalEngineering vol 110 pp 1264ndash1273 2017

[17] Q Yan B Li Y Zhang J Yan and C Zhang ldquoNumericalinvestigation of heat-insulating layers in a cold region tunneltaking into account airflow and heat transferrdquo Applied Sci-ences vol 7 no 7 p 679 2017

[18] Q Feng B-S Jiang Q Zhang and G Wang ldquoReliabilityresearch on the 5-cm-thick insulation layer used in theYuximolegai tunnel based on a physical model testrdquo ColdRegions Science and Technology vol 124 pp 54ndash66 2016

[19] X Zhang Z Zhou J Li Y Zhou and F Han ldquoA physicalmodel experiment for investigating into temperature redis-tribution in surrounding rock of permafrost tunnelrdquo ColdRegions Science and Technology vol 151 pp 47ndash52 2018

[20] Y Zeng K Liu X Zhou and L Fan ldquoTunnel temperaturefields analysis under the couple effect of convection-con-duction in cold regionsrdquo Applied =ermal Engineeringvol 120 pp 378ndash392 2017

[21] L Liu Z Li X Liu and Y Li ldquoFrost front research of a cold-region tunnel considering ventilation based on a physicalmodel testrdquo Tunnelling and Underground Space Technologyvol 77 pp 261ndash279 2018

[22] G Zhang Y Guo Y Zhou et al ldquoExperimental study on thethermal performance of tunnel lining GHE under ground-water flowrdquo Applied =ermal Engineering vol 106 pp 784ndash795 2016

[23] G Zhang S Liu X Zhao et al ldquo-e coupling effect ofventilation and groundwater flow on the thermal performance

Advances in Civil Engineering 13

of tunnel lining GHEsrdquoApplied=ermal Engineering vol 112pp 595ndash605 2017

[24] Q Hu R Shi Y Hu et al ldquoMethod to evaluate the safety oftunnels through steeply inclined strata in cold regions basedon the sidewall frost heave modelrdquo Journal of Performance ofConstructed Facilities vol 32 2018

[25] H Cai P Li and Z Wu ldquoModel test of liquid nitrogenfreezing-temperature field of improved plastic freezing piperdquoJournal of Cold Regions Engineering vol 34 no 1 2020

[26] S E A Gehlin and G Hellstrom ldquoInfluence on thermalresponse test by groundwater flow in vertical fractures in hardrockrdquo Renewable Energy vol 28 no 14 pp 2221ndash2238 2003

14 Advances in Civil Engineering

Data logger

Return pipe

Geotextile

Pump

40

60

Temperature sensorUltrasonic anemometer

4 5TS9

TS3

TS1TL4

TS5

30

TA

37

40

TS7TS8

TS6

20183

TS4

TS2TS10TS11

Plastic permeableboard

Constanttemperature

tank

Insulationlayer

Water supply pipe

Thermal insulationtank

Liftingplatform

Flow meter

(a)

Thermal insulation pipe

Air blower

TA

TS8

TS3

120

TS7 37

4040

TS1

Refrigerator

Thermal insulationbox

Temperature sensorUltrasonic anemometer

(b)

Figure 2 Model test design (a) cross section and (b) vertical section

4 Advances in Civil Engineering

241 Tunnel Model -e tunnel model consists of a14mtimes 12mtimes 12m stainless steel box and a 18m concretetube with an outer diameter of 40 cm and a thickness of 2 cm-e concrete tube which has a circular cross section is made ofcement sand gravel and water in a ratio of 1 24 36 065Sand is used in the test -e sand-raining method is used to fillthe tunnel model with sand from the Yangtze River the densityand thermal conductivities of which are 205 gcm3 and158W(mmiddotdegC) respectively To minimize the heat transferboundary effect a 5-cm thick thermal insulation layer is in-stalled around the outer surface of the stainless steel box -eplastic permeable boards are installed at the top and bottom ofthe stainless steel box to ensure that the groundwater seepagespreads over the surrounding rock -e permeable plasticboards are wrapped with geotextile to prevent the groundwaterseepage from carrying away the sand

242 Tunnel Ventilation System -e ventilation systemconsists of a refrigerator an air blower a thermal insulationbox and a thermal insulation pipe-e thermal insulation pipeconnects the air blower the thermal insulation box and theconcrete tube to form closed circulation ventilation ducts -eair blower is installed on the top of the thermal insulation boxand the refrigerator is installed in the thermal insulation box-e air inside the refrigerator can be cooled to minus30degC and theairflow velocity in the ducts can reach 4ms

243 Groundwater Seepage System -e groundwaterseepage system consists of a constant temperature watertank a pump two thermal insulation water tanks two liftingplatforms a water supply pipe and a return pipe -e watersupply pipe and return pipe connect the constant temper-ature water tank the pump the thermal insulation watertanks and the stainless steel box to form a closed circulationsystem Both thermal insulation water tanks are placed onthe lifting platforms -e groundwater seepage velocity iscontrolled by adjusting the height difference between thetwo thermal insulation water tanks

244 Measuring System To monitor the temperature var-iations in the air surrounding rock and the interface be-tween the tunnel lining and surrounding rock a temperaturemonitoring cross section is installed in the middle of themodel box -e platinum resistance temperature sensor TAis installed in the center of the concrete tube to monitor thetemperature of the airflow -e platinum resistance tem-perature sensors TS7 to TS11 are installed in the sand tomonitor the temperature variation of the surrounding rocktemperature field at different positions and depths -eplatinum resistance temperature sensors TS1 to TS6 areinstalled on the concrete tube surface equally spaced alongthe cross section to monitor the temperature variation of theinterface between the tunnel lining and surrounding rock

Water tank

Tunnelmodel box

Data logger

Thermalinsulation pipe

Thermalinsulation

box

Refrigerator

Figure 3 Model test setup

Table 1 Model test equipment and devices

Item SpecificationConstant temperature tank Heating power is 6 kW volume is 1000 LPump Water head is 9m flow velocity is 30 Lmin-ermal insulation tank Volume is 18 LAir blower Maximum wind speed is 4msTemperature sensor Resistance temperature detector (HSRTD-3-100-A) with an accuracy of plusmn 015degCFlow meter Liquid mass flow meter (DMF-1-1-A) with a precision of plusmn 02 measurement scope is 0ndash40 kghUltrasonic anemometer Measurement scope is 0ndash40ms accuracy is 001msRefrigerator Refrigerating power is 2 kW minimum temperature is minus30degC

Advances in Civil Engineering 5

-e wind speed is monitored using an ultrasonic ane-mometer that is placed at the tunnel exit Finally the liquidmass flow meter is connected to the water return pipe of thegroundwater seepage system

25 Model Test Strategy Two factors are considered in themodel test namely wind speed and groundwater seepagevelocity Zhang et al [22] presented a systematic study of theheat transfer in tunnels under groundwater seepageGroundwater seepage velocities of less than 0864md hadnegligible effects on the temperature field of the surroundingrock -us groundwater seepage velocities of 0 0923 and2743md are chosen for this model-e average wind speedof the tunnel in the Inner Mongolia Autonomous Regionand in Hebei Province is 22ms and 24ms respectively-us wind speeds of 0606 1002 and 2398ms are chosenfor this model Table 2 presents the model test strategy -eexperiment time of each test is different as groundwaterseepage can prevent the surrounding rock from freezingHence the time that the temperature of surrounding rockdown to 0degC varies with groundwater seepage velocities -eexperiment times of 115 23 and 325 h for groundwaterseepage velocities of 0 0923 and 2743md respectively arechosen for this model-ese experiment times can guaranteea part of the surrounding rock around the lining will freeze

3 Results and Discussion

31 Effect of Groundwater Seepage on the Tunnel AirTemperature Figure 4 presents the variations in tunnel airtemperature over time under the effects of groundwaterseepage and ventilation in the model test Specifically itshows that the air temperature in the tunnel decreasesFurthermore the air temperature reduction rate decreasesover time and the temperature curve fluctuates every 12 hdue to the deicing of the refrigeration equipment Figure 4also shows that groundwater seepage velocity and windspeed have significant influences on tunnel air temperatureFigure 5 presents the variations in tunnel air temperature forvarious groundwater seepage velocities at different windspeeds after cooling for 115 h In Figure 5 the air tem-perature in the tunnel increases almost linearly as thegroundwater seepage velocity increases Furthermore theeffect of groundwater seepage velocity on air temperature inthe tunnel is related to wind speed -e lowest air tem-perature in the tunnel is minus2255degC under a groundwaterseepage velocity of 0ms and a wind speed of 0606ms -ehighest air temperature in the tunnel is minus1458degC under agroundwater seepage velocity of 2743md and a wind speedof 2398ms -us the higher the groundwater seepagevelocity and wind speed are the higher the air temperature isin the tunnel

-e above analysis shows that groundwater seepage has asignificant effect on the air temperature in a tunnel -ehigher the groundwater seepage velocity is the higher the airtemperature is in the tunnel Low air temperature in a tunnelmay induce tunnel freezing damage -e thickness andlength of the tunnel insulation layer are determined by the

air temperature in the tunnel Specifically the lower the airtemperature is in the tunnel the thicker and longer thetunnel insulation layer needs to be to avoid freezing damageIt can be speculated that groundwater seepage has a sig-nificant influence on the thickness and length of the tunnelinsulation layer in cold regions causing it to thin and short-us the influence of groundwater seepage should beconsidered when designing the insulation layers of coldregion tunnels

32 Effect of Groundwater Seepage on the Surrounding RockTemperature Figure 6 presents the variations in the sur-rounding rock temperature over time under the influence ofgroundwater seepage and ventilation in the model testSpecifically it shows that the surrounding rock temperatureat TS9 TS10 and TS11 decreases -e cooling rates andamplitudes of the surrounding rock temperature differsignificantly between TS9 TS10 and TS11 -e cooling rate

Table 2 Model test strategy

Test no Groundwater seepage velocity (md) Wind speed (ms)1

00606

2 10023 23984

09230606

5 10026 23987

27430606

8 10029 2398

Deicing of refrigeratorDeicing of refrigerator Groundwater

seepage

TA 18cm

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

5 10 15 20 25 300Time (h)

ndash25

ndash20

ndash15

ndash10

ndash5

0

5

10

15

Tem

pera

ture

(degC)

Figure 4 Variations in the tunnel air temperature over time

6 Advances in Civil Engineering

and amplitude of the surrounding rock temperature arerelated to the depth of the tunnel surrounding rock thegroundwater seepage velocity and the wind speed -ecooling rate and amplitude of the surrounding rock tem-perature at the TS9 monitoring point are the largest andthose at the TS11 monitoring point are the smallest -usthe deeper the tunnel surrounding rock is the lower thecooling rate and amplitude of the tunnel surrounding rocktemperature are Lower groundwater seepage velocities andhigher wind speeds lead to greater cooling rates and am-plitudes of the surrounding rock temperature -e influenceof groundwater seepage and tunnel ventilation on thesurrounding rock temperature field is related to the depth ofthe surrounding rock -e increase in wind speed has astrong influence on the temperature field at TS9 and TS10but a weak influence on that at TS11 Figure 6 also shows thatthe wind speed has the most significant influence on thesurrounding rock temperature field when the groundwaterseepage velocity is 0923md but has the least significantinfluence on the surrounding rock temperature field whenthe groundwater seepage velocity is 0md -is can beexplained by the coupling effect of groundwater seepage andtunnel ventilation

Figure 7 presents the variations in the surrounding rocktemperature drops under groundwater seepage velocities atdifferent wind speeds after 115h of cooling It also shows thatthe temperature drops in the tunnel surrounding rock decreaseas the groundwater seepage velocity increases -e temperaturedrops differ at TS9 TS10 and TS11 under different windspeeds -e temperature drop at TS11 at different wind speedsdecreases linearly as the groundwater seepage velocity increasesAt wind speeds of 0606ms and 1002ms the temperaturedrops at TS9 and TS10 decrease linearly as the groundwaterseepage velocity increases At a wind speed of 2398ms andgroundwater seepage velocity under 0923md the temperaturedrops at TS9 and TS10 slowly decrease as the groundwater

seepage velocity increases At a wind speed of 2398ms andgroundwater seepage velocity over 0923md the temperaturedrops at TS9 and TS10 sharply decrease as the groundwaterseepage velocity increases

-e above analysis shows that groundwater seepage andtunnel ventilation have a coupling effect on the surroundingrock temperature Specifically higher groundwater seepagevelocities and lower wind speeds lead to higher surroundingrock temperatures -us the coupling influence ofgroundwater seepage and tunnel ventilation should beconsidered when designing the insulation layers of coldregion tunnels

33 Effect of Groundwater Seepage on the Temperature at theInterface between the Lining and Surrounding RockFigure 8 presents the temperature variation over time at theinterface between the lining and surrounding rock under theinfluence of groundwater seepage and ventilation in themodel test It shows that the interface temperatures of TS1TS3 TS4 TS5 and TS6 decrease over time when ground-water seepage and ventilation are considered in the modeltest Groundwater seepage has a significant effect on theinterface temperature -e effect is related to the location ofthe monitoring points -erefore the cooling rates andamplitudes of the interface temperature for TS1 TS3 TS4TS5 and TS6 differ significantly -e groundwater seepagehas the most significant effects on measuring points TS3 andTS4 and has the least significant effects on measuring pointsTS1 and TS6 Wind speed also has a significant effect on theinterface temperature -e effect is related to the ground-water seepage velocity -ese results indicate that ground-water seepage and tunnel ventilation have a coupling effecton the interface temperature and that this coupling effect isrelated to the interface location

Figure 9 shows the variations in the temperature drops atTS1 TS3 TS4 TS5 and TS6 with groundwater seepagevelocity under tunnel ventilation after 115 h of cooling Itshows that the temperature drops at TS3 and TS4 upstreamof the groundwater seepage field decrease as the ground-water seepage velocity increases However the temperaturedrops at TS1 and TS6 downstream of the groundwaterseepage field increase as the groundwater seepage velocityincreases from 0 to 0923md Furthermore the temperaturedrops at TS1 and TS6 decrease as the groundwater seepagevelocity increases from 0923 to 2743md -e smallesttemperature drop occurs at TS3 (upstream of the ground-water seepage field) and the largest temperature drop occursat TS1 (downstream of the groundwater seepage field) undergroundwater seepage -ese results indicate that ground-water seepage leads to an uneven temperature distribution atthe interface between the lining and surrounding rock andthat tunnel ventilation enhances this uneven distribution

Figure 10 presents the temperature differences betweenTS3TS5 and TS6 -e temperature at TS3 is higher undergroundwater seepage than those at TS5 and TS6 -e interfacetemperature upstream of the groundwater field is higher thanthat downstream Figure 10 also shows that the temperaturedifference between TS3 and TS6 increases as the groundwater

Wind speed = 0606msWind speed = 1002msWind speed = 2389ms

Groundwater seepage

TA 18cm

ndash22

ndash21

ndash20

ndash19

ndash18

ndash17

ndash16

ndash15

Tem

pera

ture

(degC)

05 10 15 20 25 3000Groundwater seepage velocity (md)

Figure 5 Variations in the tunnel air temperature after 115 h ofcooling

Advances in Civil Engineering 7

Deicing of refrigerator Deicing of refrigerator

0 5 10 15 20 25 30Time (h)

0

2

4

6

8

10

12

14Te

mpe

ratu

re (deg

C)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(a)

Deicing of refrigeratorDeicing of refrigerator

0

2

4

6

8

10

12

14

Tem

pera

ture

(degC)

5 10 15 20 25 300Time (h)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(b)

Deicing of refrigerator

Groundwater seepage

TA TS9

1cm4cm 5cm

TS10 TS1118cm

Deicing of refrigerator

0

2

4

6

8

10

12

Tem

pera

ture

(degC)

5 10 15 20 25 300Time (h)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(c)

Figure 6 Variations in the surrounding rock temperature over time

8 Advances in Civil Engineering

seepage velocity increases -us the higher the groundwaterseepage velocity is the higher the temperature difference isbetween TS3 and TS6-e temperature difference between TS3and TS5 increases as the groundwater seepage velocity increasesfrom 0 to 0923md and decreases as the groundwater seepagevelocity increases from 0923 to 2743md Groundwaterseepage has a great effect on the interface temperature -iseffect has a spatial difference -us both the shape and size ofthe cross section of the tunnel significantly affect the interfacetemperature under groundwater seepage

34 Effect of Groundwater Seepage on the Freezing Damage toCold Region Tunnels -e tunnel drainage system is lo-cated between the lining and the surrounding rock

Monitoring points TS3 TS5 and TS6 are located at thetop middle and foot of the tunnel drainage systemrespectively -e temperatures at TS3 TS5 and TS6determine the antifreezing ability of cold region tunnels-erefore the higher the temperatures at TS3 TS5 andTS6 are the stronger the antifreezing capability of thetunnel in cold regions is Figure 8 shows that when thegroundwater seepage velocity is 0 md the measuringpoints TS3 TS5 and TS6 freeze synchronously If thetunnel surrounding rock is free of frost heaving coldregion tunnels may not need a thermal insulation layerWhen the groundwater seepage velocity is 0923 md themonitoring point TS6 freezes first -e interface thengradually freezes from TS6 to TS5 along the circumfer-ential direction of the tunnel section -is explains why

Tem

pera

ture

dro

p (deg

C)

Groundwater seepage

TS9TS10TS11

0

2

4

6

8

10

12

05 10 15 20 25 3000

18cm TA TS9 TS104cm

1cm5cm

TS11

Groundwater seepage velocity (md)

(a)

Tem

pera

ture

dro

p (deg

C)

TS9TS10TS11

Groundwater seepage

18cm TA TS9 TS104cm

1cm5cm

TS11

0

2

4

6

8

10

12

05 10 15 20 25 3000Groundwater seepage velocity (md)

(b)

Tem

pera

ture

dro

p (deg

C)

TS9TS10TS11

Groundwater seepage

18cm TA TS9 TS104cm

1cm5cm

TS11

0

2

4

6

8

10

12

05 10 15 20 25 3000Groundwater seepage velocity (md)

(c)

Figure 7 Variations in the surrounding rock temperature drop at different groundwater seepage velocities after 115 h of cooling Averagewind speed of (a) 0606ms (b) 1002ms and (c) 2398ms

Advances in Civil Engineering 9

ndash202468

101214

ndash202468

1012

Deicing of refrigeratorDeicing of refrigerator0degC

Deicing of refrigeratorDeicing of refrigerator

Deicing of refrigerator

0degC

Tem

pera

ture

(degC)

Tem

pera

ture

(degC)

ndash202468

101214

ndash202468

1012

Tem

pera

ture

(degC)

Tem

pera

ture

(degC)

Deicing of refrigerator Deicing of refrigerator

0degC 0degC

Deicing of refrigerator

0 5 10 15 20 25 30 0 5 10 15 20 25 30Time (h) Time (h)

0 5 10 15 20 25 30 0 5 10 15 20 25 30Time (h) Time (h)

(e)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(c) (d)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(a) (b)

ndash202468

1012

Tem

pera

ture

(degC)

ndash202468

1012

Tem

pera

ture

(degC)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Groundwater seepage

Deicing of refrigerator Deicing of refrigerator

0degC

0 5 10 15 20 25 30 0 5 10 15 20 25 30Time (h) Time (h)

TS1

TS6

TS5

TS4

TS3

18cmTA45deg

45deg

Figure 8 Variations in the temperature at the interface between the lining and the surrounding rock (a) TS1 (b) TS3 (c) TS4 (d) TS5 and(e) TS6

10 Advances in Civil Engineering

cold region tunnels suffer tunnel lining leakage and roadicing -e results of the model test reveal the cause oftunnel lining leakage and road icing To avoid tunnelleakage in cold region tunnels a thermal insulation layershould be properly designed and a heating device shouldbe installed in its longitudinal drainage pipe when thegroundwater seepage velocity is low When thegroundwater seepage velocity is 2743md the moni-toring point at TS6 freezes but the monitoring points atTS3 and TS5 do not Furthermore their temperatures do

not decrease significantly as cooling time increases-erefore the tunnel has good antifreezing capabilitywhen the groundwater seepage velocity is high -is goodantifreezing capability should be fully utilized Further-more the foot of the tunnel drainage system should bestrengthened against freezing via an insulation layer andheating device

-e above analysis demonstrates that cold region tunnelshave an antifreezing capability that is mainly related to the frostheaving of the surrounding rock and the groundwater seepage

Groundwater seepage

TS1TS3TS4

TS5TS6

Tem

pera

ture

dro

p (deg

C)

TA

TS3TS4

TS5

TS6TS1

45deg45deg

18cm

2

4

6

8

10

12

14

05 10 15 20 25 3000Groundwater seepage velocity (md)

(a)

TS1TS3TS4

TS5TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3TS4

TS5

TS6TS1

45deg45deg

18cm

2

4

6

8

10

12

14

05 10 15 20 25 3000Groundwater seepage velocity (md)

(b)

TS1TS3TS4

TS5TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3TS4

TS5

TS6TS1

45deg45deg

18cm

2

4

6

8

10

12

14

05 10 15 20 25 3000Groundwater seepage velocity (md)

(c)

Figure 9 Variations in the surrounding rock temperature drop at different groundwater seepage velocities after 115 h of cooling Averagewind speed of (a) 0606ms (b) 1002ms and (c) 2398ms

Advances in Civil Engineering 11

velocity -is antifreezing capability should be fully utilized inthe antifreezing design of cold region tunnels

4 Conclusions

A systematic study on the temperature field of cold regiontunnels is presented in which a model test that considers thecoupling effects of groundwater seepage and tunnel venti-lation is conducted -e effects of groundwater seepage onthe air temperature in the tunnel the surrounding rocktemperature the temperature at the interface between thelining and surrounding rock and the freezing damage of thetunnel in cold regions are studied -e following four mainconclusions are drawn

First groundwater seepage has a significant effect on theair temperature in the tunnel -e higher the groundwater

seepage velocity the higher the air temperature in thetunnel Groundwater seepage has a significant influence onthe thickness and length of the tunnel insulation layer in coldregions -e thickness and length of the tunnel insulationlayer can decrease under groundwater seepage

Second groundwater seepage and tunnel ventilationhave a coupling effect on the surrounding rock temperatureHigher groundwater seepage velocity and lower wind speedlead to higher surrounding rock temperature -e influenceof groundwater seepage and tunnel ventilation on thesurrounding rock temperature field is related to the depth ofthe surrounding rock

-ird groundwater seepage leads to an uneven tem-perature distribution at the interface between the lining andsurrounding rock -e tunnel ventilation further enhancesthis uneven temperature distribution -e groundwater

TS3-TS5TS3-TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3

TS5

TS6

45deg 18cm

ndash1

0

1

2

3

4

5

6

7

8

9

05 10 15 20 25 3000Groundwater seepage velocity (md)

(a)

TS3-TS5TS3-TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3

TS5

TS6

45deg 18cm

ndash1

0

1

2

3

4

5

6

7

8

9

05 10 15 20 25 3000Groundwater seepage velocity (md)

(b)

TS3-TS5TS3-TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3

TS5

TS6

45deg 18cm

ndash1

0

1

2

3

4

5

6

7

8

9

05 10 15 20 25 3000Groundwater seepage velocity (md)

(c)

Figure 10 Relationships between the temperature differences at TS5 TS6 and TS3 and groundwater seepage velocity Average wind speedof (a) 0606ms (b) 1002ms and (c) 2398ms

12 Advances in Civil Engineering

seepage and tunnel ventilation have a coupling effect on theinterface temperature -is coupling effect is related to theinterface location -e influence of the groundwater seepagevelocity on the interface temperature has a spatial difference-e shape and size of the cross section of the tunnel have asignificant influence on the interface temperature undergroundwater seepage

Fourth cold region tunnels have an antifreezing capa-bility that is mainly related to the frost heaving of thesurrounding rock and the groundwater seepage velocity-eantifreezing capability of the tunnel should be fully utilizedin the antifreezing design of cold region tunnels

Data Availability

-e data used to support the findings of this study areavailable from the corresponding author upon request

Conflicts of Interest

-e authors declare that they have no conflicts of interest

Acknowledgments

-is study was supported by the Key Laboratory of Geo-technical and Underground Engineering of Ministry ofEducation Tongji University (No KLE-TJGE-B1605) theKey Laboratory of Rock Mechanics and Geohazards ofZhejiang Province (No ZJRM-2018-Y-01) and the SichuanScience and Technology Program (No 2018GZ0359)

References

[1] S Li M Zhang W Pei and Y Lai ldquoExperimental and nu-merical simulations on heat-water-mechanics interactionmechanism in a freezing soilrdquo Applied =ermal Engineeringvol 132 pp 209ndash220 2018

[2] S Li M Zhang Y Tian W Pei and H Zhong ldquoExperimentaland numerical investigations on frost damage mechanism of acanal in cold regionsrdquo Cold Regions Science and Technologyvol 116 pp 1ndash11 2015

[3] S Shen C Xia J Huang and Y Li ldquoInfluence of seasonal meltlayer depth on the stability of surrounding rock in permafrostregions based on the measurementrdquoNatural Hazards vol 75no 3 pp 2545ndash2557 2015

[4] K-J Jun Y-C Hwang and C-Y Yune ldquoField measurementof temperature inside tunnel in winter in Gangwon KoreardquoCold Regions Science and Technology vol 143 pp 32ndash42 2017

[5] Q Ma X Luo Y Lai F Niu and J Gao ldquoNumerical in-vestigation on thermal insulation layer of a tunnel in sea-sonally frozen regionsrdquoApplied=ermal Engineering vol 138pp 280ndash291 2018

[6] X Zhao X Yang H Zhang H Lai and X Wang ldquoAnanalytical solution for frost heave force by the multifactor ofcoupled heat and moisture transfer in cold-region tunnelsrdquoCold Regions Science and Technology vol 175 2020

[7] Y M Lai S Y Liu Z W Wu and W Yu ldquoApproximateanalytical solution for temperature fields in cold regionscircular tunnelsrdquoCold Regions Science and Technology vol 34no 1 pp 43ndash49 2002

[8] G Zhang C Xia M Sun Y Zou and S Xiao ldquoA new modeland analytical solution for the heat conduction of tunnel

lining ground heat exchangersrdquo Cold Regions Science andTechnology vol 88 pp 59ndash66 2013

[9] Y M Lai Z W Wu Y L Zhu and L N Zhu ldquoNonlinearanalysis for the coupled problem of temperature seepage andstress fields in cold-region tunnelsrdquo Tunnelling and Under-ground Space Technology vol 13 no 4 pp 435ndash440 1998

[10] X Zhang J Xiao Y Zhang et al ldquoStudy of the function of theinsulation layer for treating water leakage in permafrosttunnelsrdquo Applied =ermal Engineering vol 27 no 2-3pp 637ndash645 2007

[11] X Zhang Y Lai W Yu and S Zhang ldquoNon-linear analysisfor the freezing-thawing situation of the rock surrounding thetunnel in cold regions under the conditions of differentconstruction seasons initial temperatures and insulationsrdquoTunnelling and Underground Space Technology vol 17 no 3pp 315ndash325 2002

[12] X Zhang Y Lai W Yu and Y Wu ldquoForecast analysis for there-frozen of Feng Huoshan permafrost tunnel on Qing-Zangrailwayrdquo Tunnelling and Underground Space Technologyvol 19 no 1 pp 45ndash56 2004

[13] X Tan W Chen H Tian and J Cao ldquoWater flow and heattransport including icewater phase change in porous medianumerical simulation and applicationrdquo Cold Regions Scienceand Technology vol 68 no 1-2 pp 74ndash84 2011

[14] X Tan W Chen G Wu and J Yang ldquoNumerical simulationsof heat transfer with ice-water phase change occurring inporous media and application to a cold-region tunnelrdquoTunnelling and Underground Space Technology vol 38pp 170ndash179 2013

[15] X Tan W Chen D Yang et al ldquoStudy on the influence ofairflow on the temperature of the surrounding rock in a coldregion tunnel and its application to insulation layer designrdquoApplied =ermal Engineering vol 67 no 1-2 pp 320ndash3342014

[16] S Li F Niu Y Lai W Pei and W Yu ldquoOptimal design ofthermal insulation layer of a tunnel in permafrost regionsbased on coupled heat-water simulationrdquo Applied =ermalEngineering vol 110 pp 1264ndash1273 2017

[17] Q Yan B Li Y Zhang J Yan and C Zhang ldquoNumericalinvestigation of heat-insulating layers in a cold region tunneltaking into account airflow and heat transferrdquo Applied Sci-ences vol 7 no 7 p 679 2017

[18] Q Feng B-S Jiang Q Zhang and G Wang ldquoReliabilityresearch on the 5-cm-thick insulation layer used in theYuximolegai tunnel based on a physical model testrdquo ColdRegions Science and Technology vol 124 pp 54ndash66 2016

[19] X Zhang Z Zhou J Li Y Zhou and F Han ldquoA physicalmodel experiment for investigating into temperature redis-tribution in surrounding rock of permafrost tunnelrdquo ColdRegions Science and Technology vol 151 pp 47ndash52 2018

[20] Y Zeng K Liu X Zhou and L Fan ldquoTunnel temperaturefields analysis under the couple effect of convection-con-duction in cold regionsrdquo Applied =ermal Engineeringvol 120 pp 378ndash392 2017

[21] L Liu Z Li X Liu and Y Li ldquoFrost front research of a cold-region tunnel considering ventilation based on a physicalmodel testrdquo Tunnelling and Underground Space Technologyvol 77 pp 261ndash279 2018

[22] G Zhang Y Guo Y Zhou et al ldquoExperimental study on thethermal performance of tunnel lining GHE under ground-water flowrdquo Applied =ermal Engineering vol 106 pp 784ndash795 2016

[23] G Zhang S Liu X Zhao et al ldquo-e coupling effect ofventilation and groundwater flow on the thermal performance

Advances in Civil Engineering 13

of tunnel lining GHEsrdquoApplied=ermal Engineering vol 112pp 595ndash605 2017

[24] Q Hu R Shi Y Hu et al ldquoMethod to evaluate the safety oftunnels through steeply inclined strata in cold regions basedon the sidewall frost heave modelrdquo Journal of Performance ofConstructed Facilities vol 32 2018

[25] H Cai P Li and Z Wu ldquoModel test of liquid nitrogenfreezing-temperature field of improved plastic freezing piperdquoJournal of Cold Regions Engineering vol 34 no 1 2020

[26] S E A Gehlin and G Hellstrom ldquoInfluence on thermalresponse test by groundwater flow in vertical fractures in hardrockrdquo Renewable Energy vol 28 no 14 pp 2221ndash2238 2003

14 Advances in Civil Engineering

241 Tunnel Model -e tunnel model consists of a14mtimes 12mtimes 12m stainless steel box and a 18m concretetube with an outer diameter of 40 cm and a thickness of 2 cm-e concrete tube which has a circular cross section is made ofcement sand gravel and water in a ratio of 1 24 36 065Sand is used in the test -e sand-raining method is used to fillthe tunnel model with sand from the Yangtze River the densityand thermal conductivities of which are 205 gcm3 and158W(mmiddotdegC) respectively To minimize the heat transferboundary effect a 5-cm thick thermal insulation layer is in-stalled around the outer surface of the stainless steel box -eplastic permeable boards are installed at the top and bottom ofthe stainless steel box to ensure that the groundwater seepagespreads over the surrounding rock -e permeable plasticboards are wrapped with geotextile to prevent the groundwaterseepage from carrying away the sand

242 Tunnel Ventilation System -e ventilation systemconsists of a refrigerator an air blower a thermal insulationbox and a thermal insulation pipe-e thermal insulation pipeconnects the air blower the thermal insulation box and theconcrete tube to form closed circulation ventilation ducts -eair blower is installed on the top of the thermal insulation boxand the refrigerator is installed in the thermal insulation box-e air inside the refrigerator can be cooled to minus30degC and theairflow velocity in the ducts can reach 4ms

243 Groundwater Seepage System -e groundwaterseepage system consists of a constant temperature watertank a pump two thermal insulation water tanks two liftingplatforms a water supply pipe and a return pipe -e watersupply pipe and return pipe connect the constant temper-ature water tank the pump the thermal insulation watertanks and the stainless steel box to form a closed circulationsystem Both thermal insulation water tanks are placed onthe lifting platforms -e groundwater seepage velocity iscontrolled by adjusting the height difference between thetwo thermal insulation water tanks

244 Measuring System To monitor the temperature var-iations in the air surrounding rock and the interface be-tween the tunnel lining and surrounding rock a temperaturemonitoring cross section is installed in the middle of themodel box -e platinum resistance temperature sensor TAis installed in the center of the concrete tube to monitor thetemperature of the airflow -e platinum resistance tem-perature sensors TS7 to TS11 are installed in the sand tomonitor the temperature variation of the surrounding rocktemperature field at different positions and depths -eplatinum resistance temperature sensors TS1 to TS6 areinstalled on the concrete tube surface equally spaced alongthe cross section to monitor the temperature variation of theinterface between the tunnel lining and surrounding rock

Water tank

Tunnelmodel box

Data logger

Thermalinsulation pipe

Thermalinsulation

box

Refrigerator

Figure 3 Model test setup

Table 1 Model test equipment and devices

Item SpecificationConstant temperature tank Heating power is 6 kW volume is 1000 LPump Water head is 9m flow velocity is 30 Lmin-ermal insulation tank Volume is 18 LAir blower Maximum wind speed is 4msTemperature sensor Resistance temperature detector (HSRTD-3-100-A) with an accuracy of plusmn 015degCFlow meter Liquid mass flow meter (DMF-1-1-A) with a precision of plusmn 02 measurement scope is 0ndash40 kghUltrasonic anemometer Measurement scope is 0ndash40ms accuracy is 001msRefrigerator Refrigerating power is 2 kW minimum temperature is minus30degC

Advances in Civil Engineering 5

-e wind speed is monitored using an ultrasonic ane-mometer that is placed at the tunnel exit Finally the liquidmass flow meter is connected to the water return pipe of thegroundwater seepage system

25 Model Test Strategy Two factors are considered in themodel test namely wind speed and groundwater seepagevelocity Zhang et al [22] presented a systematic study of theheat transfer in tunnels under groundwater seepageGroundwater seepage velocities of less than 0864md hadnegligible effects on the temperature field of the surroundingrock -us groundwater seepage velocities of 0 0923 and2743md are chosen for this model-e average wind speedof the tunnel in the Inner Mongolia Autonomous Regionand in Hebei Province is 22ms and 24ms respectively-us wind speeds of 0606 1002 and 2398ms are chosenfor this model Table 2 presents the model test strategy -eexperiment time of each test is different as groundwaterseepage can prevent the surrounding rock from freezingHence the time that the temperature of surrounding rockdown to 0degC varies with groundwater seepage velocities -eexperiment times of 115 23 and 325 h for groundwaterseepage velocities of 0 0923 and 2743md respectively arechosen for this model-ese experiment times can guaranteea part of the surrounding rock around the lining will freeze

3 Results and Discussion

31 Effect of Groundwater Seepage on the Tunnel AirTemperature Figure 4 presents the variations in tunnel airtemperature over time under the effects of groundwaterseepage and ventilation in the model test Specifically itshows that the air temperature in the tunnel decreasesFurthermore the air temperature reduction rate decreasesover time and the temperature curve fluctuates every 12 hdue to the deicing of the refrigeration equipment Figure 4also shows that groundwater seepage velocity and windspeed have significant influences on tunnel air temperatureFigure 5 presents the variations in tunnel air temperature forvarious groundwater seepage velocities at different windspeeds after cooling for 115 h In Figure 5 the air tem-perature in the tunnel increases almost linearly as thegroundwater seepage velocity increases Furthermore theeffect of groundwater seepage velocity on air temperature inthe tunnel is related to wind speed -e lowest air tem-perature in the tunnel is minus2255degC under a groundwaterseepage velocity of 0ms and a wind speed of 0606ms -ehighest air temperature in the tunnel is minus1458degC under agroundwater seepage velocity of 2743md and a wind speedof 2398ms -us the higher the groundwater seepagevelocity and wind speed are the higher the air temperature isin the tunnel

-e above analysis shows that groundwater seepage has asignificant effect on the air temperature in a tunnel -ehigher the groundwater seepage velocity is the higher the airtemperature is in the tunnel Low air temperature in a tunnelmay induce tunnel freezing damage -e thickness andlength of the tunnel insulation layer are determined by the

air temperature in the tunnel Specifically the lower the airtemperature is in the tunnel the thicker and longer thetunnel insulation layer needs to be to avoid freezing damageIt can be speculated that groundwater seepage has a sig-nificant influence on the thickness and length of the tunnelinsulation layer in cold regions causing it to thin and short-us the influence of groundwater seepage should beconsidered when designing the insulation layers of coldregion tunnels

32 Effect of Groundwater Seepage on the Surrounding RockTemperature Figure 6 presents the variations in the sur-rounding rock temperature over time under the influence ofgroundwater seepage and ventilation in the model testSpecifically it shows that the surrounding rock temperatureat TS9 TS10 and TS11 decreases -e cooling rates andamplitudes of the surrounding rock temperature differsignificantly between TS9 TS10 and TS11 -e cooling rate

Table 2 Model test strategy

Test no Groundwater seepage velocity (md) Wind speed (ms)1

00606

2 10023 23984

09230606

5 10026 23987

27430606

8 10029 2398

Deicing of refrigeratorDeicing of refrigerator Groundwater

seepage

TA 18cm

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

5 10 15 20 25 300Time (h)

ndash25

ndash20

ndash15

ndash10

ndash5

0

5

10

15

Tem

pera

ture

(degC)

Figure 4 Variations in the tunnel air temperature over time

6 Advances in Civil Engineering

and amplitude of the surrounding rock temperature arerelated to the depth of the tunnel surrounding rock thegroundwater seepage velocity and the wind speed -ecooling rate and amplitude of the surrounding rock tem-perature at the TS9 monitoring point are the largest andthose at the TS11 monitoring point are the smallest -usthe deeper the tunnel surrounding rock is the lower thecooling rate and amplitude of the tunnel surrounding rocktemperature are Lower groundwater seepage velocities andhigher wind speeds lead to greater cooling rates and am-plitudes of the surrounding rock temperature -e influenceof groundwater seepage and tunnel ventilation on thesurrounding rock temperature field is related to the depth ofthe surrounding rock -e increase in wind speed has astrong influence on the temperature field at TS9 and TS10but a weak influence on that at TS11 Figure 6 also shows thatthe wind speed has the most significant influence on thesurrounding rock temperature field when the groundwaterseepage velocity is 0923md but has the least significantinfluence on the surrounding rock temperature field whenthe groundwater seepage velocity is 0md -is can beexplained by the coupling effect of groundwater seepage andtunnel ventilation

Figure 7 presents the variations in the surrounding rocktemperature drops under groundwater seepage velocities atdifferent wind speeds after 115h of cooling It also shows thatthe temperature drops in the tunnel surrounding rock decreaseas the groundwater seepage velocity increases -e temperaturedrops differ at TS9 TS10 and TS11 under different windspeeds -e temperature drop at TS11 at different wind speedsdecreases linearly as the groundwater seepage velocity increasesAt wind speeds of 0606ms and 1002ms the temperaturedrops at TS9 and TS10 decrease linearly as the groundwaterseepage velocity increases At a wind speed of 2398ms andgroundwater seepage velocity under 0923md the temperaturedrops at TS9 and TS10 slowly decrease as the groundwater

seepage velocity increases At a wind speed of 2398ms andgroundwater seepage velocity over 0923md the temperaturedrops at TS9 and TS10 sharply decrease as the groundwaterseepage velocity increases

-e above analysis shows that groundwater seepage andtunnel ventilation have a coupling effect on the surroundingrock temperature Specifically higher groundwater seepagevelocities and lower wind speeds lead to higher surroundingrock temperatures -us the coupling influence ofgroundwater seepage and tunnel ventilation should beconsidered when designing the insulation layers of coldregion tunnels

33 Effect of Groundwater Seepage on the Temperature at theInterface between the Lining and Surrounding RockFigure 8 presents the temperature variation over time at theinterface between the lining and surrounding rock under theinfluence of groundwater seepage and ventilation in themodel test It shows that the interface temperatures of TS1TS3 TS4 TS5 and TS6 decrease over time when ground-water seepage and ventilation are considered in the modeltest Groundwater seepage has a significant effect on theinterface temperature -e effect is related to the location ofthe monitoring points -erefore the cooling rates andamplitudes of the interface temperature for TS1 TS3 TS4TS5 and TS6 differ significantly -e groundwater seepagehas the most significant effects on measuring points TS3 andTS4 and has the least significant effects on measuring pointsTS1 and TS6 Wind speed also has a significant effect on theinterface temperature -e effect is related to the ground-water seepage velocity -ese results indicate that ground-water seepage and tunnel ventilation have a coupling effecton the interface temperature and that this coupling effect isrelated to the interface location

Figure 9 shows the variations in the temperature drops atTS1 TS3 TS4 TS5 and TS6 with groundwater seepagevelocity under tunnel ventilation after 115 h of cooling Itshows that the temperature drops at TS3 and TS4 upstreamof the groundwater seepage field decrease as the ground-water seepage velocity increases However the temperaturedrops at TS1 and TS6 downstream of the groundwaterseepage field increase as the groundwater seepage velocityincreases from 0 to 0923md Furthermore the temperaturedrops at TS1 and TS6 decrease as the groundwater seepagevelocity increases from 0923 to 2743md -e smallesttemperature drop occurs at TS3 (upstream of the ground-water seepage field) and the largest temperature drop occursat TS1 (downstream of the groundwater seepage field) undergroundwater seepage -ese results indicate that ground-water seepage leads to an uneven temperature distribution atthe interface between the lining and surrounding rock andthat tunnel ventilation enhances this uneven distribution

Figure 10 presents the temperature differences betweenTS3TS5 and TS6 -e temperature at TS3 is higher undergroundwater seepage than those at TS5 and TS6 -e interfacetemperature upstream of the groundwater field is higher thanthat downstream Figure 10 also shows that the temperaturedifference between TS3 and TS6 increases as the groundwater

Wind speed = 0606msWind speed = 1002msWind speed = 2389ms

Groundwater seepage

TA 18cm

ndash22

ndash21

ndash20

ndash19

ndash18

ndash17

ndash16

ndash15

Tem

pera

ture

(degC)

05 10 15 20 25 3000Groundwater seepage velocity (md)

Figure 5 Variations in the tunnel air temperature after 115 h ofcooling

Advances in Civil Engineering 7

Deicing of refrigerator Deicing of refrigerator

0 5 10 15 20 25 30Time (h)

0

2

4

6

8

10

12

14Te

mpe

ratu

re (deg

C)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(a)

Deicing of refrigeratorDeicing of refrigerator

0

2

4

6

8

10

12

14

Tem

pera

ture

(degC)

5 10 15 20 25 300Time (h)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(b)

Deicing of refrigerator

Groundwater seepage

TA TS9

1cm4cm 5cm

TS10 TS1118cm

Deicing of refrigerator

0

2

4

6

8

10

12

Tem

pera

ture

(degC)

5 10 15 20 25 300Time (h)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(c)

Figure 6 Variations in the surrounding rock temperature over time

8 Advances in Civil Engineering

seepage velocity increases -us the higher the groundwaterseepage velocity is the higher the temperature difference isbetween TS3 and TS6-e temperature difference between TS3and TS5 increases as the groundwater seepage velocity increasesfrom 0 to 0923md and decreases as the groundwater seepagevelocity increases from 0923 to 2743md Groundwaterseepage has a great effect on the interface temperature -iseffect has a spatial difference -us both the shape and size ofthe cross section of the tunnel significantly affect the interfacetemperature under groundwater seepage

34 Effect of Groundwater Seepage on the Freezing Damage toCold Region Tunnels -e tunnel drainage system is lo-cated between the lining and the surrounding rock

Monitoring points TS3 TS5 and TS6 are located at thetop middle and foot of the tunnel drainage systemrespectively -e temperatures at TS3 TS5 and TS6determine the antifreezing ability of cold region tunnels-erefore the higher the temperatures at TS3 TS5 andTS6 are the stronger the antifreezing capability of thetunnel in cold regions is Figure 8 shows that when thegroundwater seepage velocity is 0 md the measuringpoints TS3 TS5 and TS6 freeze synchronously If thetunnel surrounding rock is free of frost heaving coldregion tunnels may not need a thermal insulation layerWhen the groundwater seepage velocity is 0923 md themonitoring point TS6 freezes first -e interface thengradually freezes from TS6 to TS5 along the circumfer-ential direction of the tunnel section -is explains why

Tem

pera

ture

dro

p (deg

C)

Groundwater seepage

TS9TS10TS11

0

2

4

6

8

10

12

05 10 15 20 25 3000

18cm TA TS9 TS104cm

1cm5cm

TS11

Groundwater seepage velocity (md)

(a)

Tem

pera

ture

dro

p (deg

C)

TS9TS10TS11

Groundwater seepage

18cm TA TS9 TS104cm

1cm5cm

TS11

0

2

4

6

8

10

12

05 10 15 20 25 3000Groundwater seepage velocity (md)

(b)

Tem

pera

ture

dro

p (deg

C)

TS9TS10TS11

Groundwater seepage

18cm TA TS9 TS104cm

1cm5cm

TS11

0

2

4

6

8

10

12

05 10 15 20 25 3000Groundwater seepage velocity (md)

(c)

Figure 7 Variations in the surrounding rock temperature drop at different groundwater seepage velocities after 115 h of cooling Averagewind speed of (a) 0606ms (b) 1002ms and (c) 2398ms

Advances in Civil Engineering 9

ndash202468

101214

ndash202468

1012

Deicing of refrigeratorDeicing of refrigerator0degC

Deicing of refrigeratorDeicing of refrigerator

Deicing of refrigerator

0degC

Tem

pera

ture

(degC)

Tem

pera

ture

(degC)

ndash202468

101214

ndash202468

1012

Tem

pera

ture

(degC)

Tem

pera

ture

(degC)

Deicing of refrigerator Deicing of refrigerator

0degC 0degC

Deicing of refrigerator

0 5 10 15 20 25 30 0 5 10 15 20 25 30Time (h) Time (h)

0 5 10 15 20 25 30 0 5 10 15 20 25 30Time (h) Time (h)

(e)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(c) (d)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(a) (b)

ndash202468

1012

Tem

pera

ture

(degC)

ndash202468

1012

Tem

pera

ture

(degC)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Groundwater seepage

Deicing of refrigerator Deicing of refrigerator

0degC

0 5 10 15 20 25 30 0 5 10 15 20 25 30Time (h) Time (h)

TS1

TS6

TS5

TS4

TS3

18cmTA45deg

45deg

Figure 8 Variations in the temperature at the interface between the lining and the surrounding rock (a) TS1 (b) TS3 (c) TS4 (d) TS5 and(e) TS6

10 Advances in Civil Engineering

cold region tunnels suffer tunnel lining leakage and roadicing -e results of the model test reveal the cause oftunnel lining leakage and road icing To avoid tunnelleakage in cold region tunnels a thermal insulation layershould be properly designed and a heating device shouldbe installed in its longitudinal drainage pipe when thegroundwater seepage velocity is low When thegroundwater seepage velocity is 2743md the moni-toring point at TS6 freezes but the monitoring points atTS3 and TS5 do not Furthermore their temperatures do

not decrease significantly as cooling time increases-erefore the tunnel has good antifreezing capabilitywhen the groundwater seepage velocity is high -is goodantifreezing capability should be fully utilized Further-more the foot of the tunnel drainage system should bestrengthened against freezing via an insulation layer andheating device

-e above analysis demonstrates that cold region tunnelshave an antifreezing capability that is mainly related to the frostheaving of the surrounding rock and the groundwater seepage

Groundwater seepage

TS1TS3TS4

TS5TS6

Tem

pera

ture

dro

p (deg

C)

TA

TS3TS4

TS5

TS6TS1

45deg45deg

18cm

2

4

6

8

10

12

14

05 10 15 20 25 3000Groundwater seepage velocity (md)

(a)

TS1TS3TS4

TS5TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3TS4

TS5

TS6TS1

45deg45deg

18cm

2

4

6

8

10

12

14

05 10 15 20 25 3000Groundwater seepage velocity (md)

(b)

TS1TS3TS4

TS5TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3TS4

TS5

TS6TS1

45deg45deg

18cm

2

4

6

8

10

12

14

05 10 15 20 25 3000Groundwater seepage velocity (md)

(c)

Figure 9 Variations in the surrounding rock temperature drop at different groundwater seepage velocities after 115 h of cooling Averagewind speed of (a) 0606ms (b) 1002ms and (c) 2398ms

Advances in Civil Engineering 11

velocity -is antifreezing capability should be fully utilized inthe antifreezing design of cold region tunnels

4 Conclusions

A systematic study on the temperature field of cold regiontunnels is presented in which a model test that considers thecoupling effects of groundwater seepage and tunnel venti-lation is conducted -e effects of groundwater seepage onthe air temperature in the tunnel the surrounding rocktemperature the temperature at the interface between thelining and surrounding rock and the freezing damage of thetunnel in cold regions are studied -e following four mainconclusions are drawn

First groundwater seepage has a significant effect on theair temperature in the tunnel -e higher the groundwater

seepage velocity the higher the air temperature in thetunnel Groundwater seepage has a significant influence onthe thickness and length of the tunnel insulation layer in coldregions -e thickness and length of the tunnel insulationlayer can decrease under groundwater seepage

Second groundwater seepage and tunnel ventilationhave a coupling effect on the surrounding rock temperatureHigher groundwater seepage velocity and lower wind speedlead to higher surrounding rock temperature -e influenceof groundwater seepage and tunnel ventilation on thesurrounding rock temperature field is related to the depth ofthe surrounding rock

-ird groundwater seepage leads to an uneven tem-perature distribution at the interface between the lining andsurrounding rock -e tunnel ventilation further enhancesthis uneven temperature distribution -e groundwater

TS3-TS5TS3-TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3

TS5

TS6

45deg 18cm

ndash1

0

1

2

3

4

5

6

7

8

9

05 10 15 20 25 3000Groundwater seepage velocity (md)

(a)

TS3-TS5TS3-TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3

TS5

TS6

45deg 18cm

ndash1

0

1

2

3

4

5

6

7

8

9

05 10 15 20 25 3000Groundwater seepage velocity (md)

(b)

TS3-TS5TS3-TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3

TS5

TS6

45deg 18cm

ndash1

0

1

2

3

4

5

6

7

8

9

05 10 15 20 25 3000Groundwater seepage velocity (md)

(c)

Figure 10 Relationships between the temperature differences at TS5 TS6 and TS3 and groundwater seepage velocity Average wind speedof (a) 0606ms (b) 1002ms and (c) 2398ms

12 Advances in Civil Engineering

seepage and tunnel ventilation have a coupling effect on theinterface temperature -is coupling effect is related to theinterface location -e influence of the groundwater seepagevelocity on the interface temperature has a spatial difference-e shape and size of the cross section of the tunnel have asignificant influence on the interface temperature undergroundwater seepage

Fourth cold region tunnels have an antifreezing capa-bility that is mainly related to the frost heaving of thesurrounding rock and the groundwater seepage velocity-eantifreezing capability of the tunnel should be fully utilizedin the antifreezing design of cold region tunnels

Data Availability

-e data used to support the findings of this study areavailable from the corresponding author upon request

Conflicts of Interest

-e authors declare that they have no conflicts of interest

Acknowledgments

-is study was supported by the Key Laboratory of Geo-technical and Underground Engineering of Ministry ofEducation Tongji University (No KLE-TJGE-B1605) theKey Laboratory of Rock Mechanics and Geohazards ofZhejiang Province (No ZJRM-2018-Y-01) and the SichuanScience and Technology Program (No 2018GZ0359)

References

[1] S Li M Zhang W Pei and Y Lai ldquoExperimental and nu-merical simulations on heat-water-mechanics interactionmechanism in a freezing soilrdquo Applied =ermal Engineeringvol 132 pp 209ndash220 2018

[2] S Li M Zhang Y Tian W Pei and H Zhong ldquoExperimentaland numerical investigations on frost damage mechanism of acanal in cold regionsrdquo Cold Regions Science and Technologyvol 116 pp 1ndash11 2015

[3] S Shen C Xia J Huang and Y Li ldquoInfluence of seasonal meltlayer depth on the stability of surrounding rock in permafrostregions based on the measurementrdquoNatural Hazards vol 75no 3 pp 2545ndash2557 2015

[4] K-J Jun Y-C Hwang and C-Y Yune ldquoField measurementof temperature inside tunnel in winter in Gangwon KoreardquoCold Regions Science and Technology vol 143 pp 32ndash42 2017

[5] Q Ma X Luo Y Lai F Niu and J Gao ldquoNumerical in-vestigation on thermal insulation layer of a tunnel in sea-sonally frozen regionsrdquoApplied=ermal Engineering vol 138pp 280ndash291 2018

[6] X Zhao X Yang H Zhang H Lai and X Wang ldquoAnanalytical solution for frost heave force by the multifactor ofcoupled heat and moisture transfer in cold-region tunnelsrdquoCold Regions Science and Technology vol 175 2020

[7] Y M Lai S Y Liu Z W Wu and W Yu ldquoApproximateanalytical solution for temperature fields in cold regionscircular tunnelsrdquoCold Regions Science and Technology vol 34no 1 pp 43ndash49 2002

[8] G Zhang C Xia M Sun Y Zou and S Xiao ldquoA new modeland analytical solution for the heat conduction of tunnel

lining ground heat exchangersrdquo Cold Regions Science andTechnology vol 88 pp 59ndash66 2013

[9] Y M Lai Z W Wu Y L Zhu and L N Zhu ldquoNonlinearanalysis for the coupled problem of temperature seepage andstress fields in cold-region tunnelsrdquo Tunnelling and Under-ground Space Technology vol 13 no 4 pp 435ndash440 1998

[10] X Zhang J Xiao Y Zhang et al ldquoStudy of the function of theinsulation layer for treating water leakage in permafrosttunnelsrdquo Applied =ermal Engineering vol 27 no 2-3pp 637ndash645 2007

[11] X Zhang Y Lai W Yu and S Zhang ldquoNon-linear analysisfor the freezing-thawing situation of the rock surrounding thetunnel in cold regions under the conditions of differentconstruction seasons initial temperatures and insulationsrdquoTunnelling and Underground Space Technology vol 17 no 3pp 315ndash325 2002

[12] X Zhang Y Lai W Yu and Y Wu ldquoForecast analysis for there-frozen of Feng Huoshan permafrost tunnel on Qing-Zangrailwayrdquo Tunnelling and Underground Space Technologyvol 19 no 1 pp 45ndash56 2004

[13] X Tan W Chen H Tian and J Cao ldquoWater flow and heattransport including icewater phase change in porous medianumerical simulation and applicationrdquo Cold Regions Scienceand Technology vol 68 no 1-2 pp 74ndash84 2011

[14] X Tan W Chen G Wu and J Yang ldquoNumerical simulationsof heat transfer with ice-water phase change occurring inporous media and application to a cold-region tunnelrdquoTunnelling and Underground Space Technology vol 38pp 170ndash179 2013

[15] X Tan W Chen D Yang et al ldquoStudy on the influence ofairflow on the temperature of the surrounding rock in a coldregion tunnel and its application to insulation layer designrdquoApplied =ermal Engineering vol 67 no 1-2 pp 320ndash3342014

[16] S Li F Niu Y Lai W Pei and W Yu ldquoOptimal design ofthermal insulation layer of a tunnel in permafrost regionsbased on coupled heat-water simulationrdquo Applied =ermalEngineering vol 110 pp 1264ndash1273 2017

[17] Q Yan B Li Y Zhang J Yan and C Zhang ldquoNumericalinvestigation of heat-insulating layers in a cold region tunneltaking into account airflow and heat transferrdquo Applied Sci-ences vol 7 no 7 p 679 2017

[18] Q Feng B-S Jiang Q Zhang and G Wang ldquoReliabilityresearch on the 5-cm-thick insulation layer used in theYuximolegai tunnel based on a physical model testrdquo ColdRegions Science and Technology vol 124 pp 54ndash66 2016

[19] X Zhang Z Zhou J Li Y Zhou and F Han ldquoA physicalmodel experiment for investigating into temperature redis-tribution in surrounding rock of permafrost tunnelrdquo ColdRegions Science and Technology vol 151 pp 47ndash52 2018

[20] Y Zeng K Liu X Zhou and L Fan ldquoTunnel temperaturefields analysis under the couple effect of convection-con-duction in cold regionsrdquo Applied =ermal Engineeringvol 120 pp 378ndash392 2017

[21] L Liu Z Li X Liu and Y Li ldquoFrost front research of a cold-region tunnel considering ventilation based on a physicalmodel testrdquo Tunnelling and Underground Space Technologyvol 77 pp 261ndash279 2018

[22] G Zhang Y Guo Y Zhou et al ldquoExperimental study on thethermal performance of tunnel lining GHE under ground-water flowrdquo Applied =ermal Engineering vol 106 pp 784ndash795 2016

[23] G Zhang S Liu X Zhao et al ldquo-e coupling effect ofventilation and groundwater flow on the thermal performance

Advances in Civil Engineering 13

of tunnel lining GHEsrdquoApplied=ermal Engineering vol 112pp 595ndash605 2017

[24] Q Hu R Shi Y Hu et al ldquoMethod to evaluate the safety oftunnels through steeply inclined strata in cold regions basedon the sidewall frost heave modelrdquo Journal of Performance ofConstructed Facilities vol 32 2018

[25] H Cai P Li and Z Wu ldquoModel test of liquid nitrogenfreezing-temperature field of improved plastic freezing piperdquoJournal of Cold Regions Engineering vol 34 no 1 2020

[26] S E A Gehlin and G Hellstrom ldquoInfluence on thermalresponse test by groundwater flow in vertical fractures in hardrockrdquo Renewable Energy vol 28 no 14 pp 2221ndash2238 2003

14 Advances in Civil Engineering

-e wind speed is monitored using an ultrasonic ane-mometer that is placed at the tunnel exit Finally the liquidmass flow meter is connected to the water return pipe of thegroundwater seepage system

25 Model Test Strategy Two factors are considered in themodel test namely wind speed and groundwater seepagevelocity Zhang et al [22] presented a systematic study of theheat transfer in tunnels under groundwater seepageGroundwater seepage velocities of less than 0864md hadnegligible effects on the temperature field of the surroundingrock -us groundwater seepage velocities of 0 0923 and2743md are chosen for this model-e average wind speedof the tunnel in the Inner Mongolia Autonomous Regionand in Hebei Province is 22ms and 24ms respectively-us wind speeds of 0606 1002 and 2398ms are chosenfor this model Table 2 presents the model test strategy -eexperiment time of each test is different as groundwaterseepage can prevent the surrounding rock from freezingHence the time that the temperature of surrounding rockdown to 0degC varies with groundwater seepage velocities -eexperiment times of 115 23 and 325 h for groundwaterseepage velocities of 0 0923 and 2743md respectively arechosen for this model-ese experiment times can guaranteea part of the surrounding rock around the lining will freeze

3 Results and Discussion

31 Effect of Groundwater Seepage on the Tunnel AirTemperature Figure 4 presents the variations in tunnel airtemperature over time under the effects of groundwaterseepage and ventilation in the model test Specifically itshows that the air temperature in the tunnel decreasesFurthermore the air temperature reduction rate decreasesover time and the temperature curve fluctuates every 12 hdue to the deicing of the refrigeration equipment Figure 4also shows that groundwater seepage velocity and windspeed have significant influences on tunnel air temperatureFigure 5 presents the variations in tunnel air temperature forvarious groundwater seepage velocities at different windspeeds after cooling for 115 h In Figure 5 the air tem-perature in the tunnel increases almost linearly as thegroundwater seepage velocity increases Furthermore theeffect of groundwater seepage velocity on air temperature inthe tunnel is related to wind speed -e lowest air tem-perature in the tunnel is minus2255degC under a groundwaterseepage velocity of 0ms and a wind speed of 0606ms -ehighest air temperature in the tunnel is minus1458degC under agroundwater seepage velocity of 2743md and a wind speedof 2398ms -us the higher the groundwater seepagevelocity and wind speed are the higher the air temperature isin the tunnel

-e above analysis shows that groundwater seepage has asignificant effect on the air temperature in a tunnel -ehigher the groundwater seepage velocity is the higher the airtemperature is in the tunnel Low air temperature in a tunnelmay induce tunnel freezing damage -e thickness andlength of the tunnel insulation layer are determined by the

air temperature in the tunnel Specifically the lower the airtemperature is in the tunnel the thicker and longer thetunnel insulation layer needs to be to avoid freezing damageIt can be speculated that groundwater seepage has a sig-nificant influence on the thickness and length of the tunnelinsulation layer in cold regions causing it to thin and short-us the influence of groundwater seepage should beconsidered when designing the insulation layers of coldregion tunnels

32 Effect of Groundwater Seepage on the Surrounding RockTemperature Figure 6 presents the variations in the sur-rounding rock temperature over time under the influence ofgroundwater seepage and ventilation in the model testSpecifically it shows that the surrounding rock temperatureat TS9 TS10 and TS11 decreases -e cooling rates andamplitudes of the surrounding rock temperature differsignificantly between TS9 TS10 and TS11 -e cooling rate

Table 2 Model test strategy

Test no Groundwater seepage velocity (md) Wind speed (ms)1

00606

2 10023 23984

09230606

5 10026 23987

27430606

8 10029 2398

Deicing of refrigeratorDeicing of refrigerator Groundwater

seepage

TA 18cm

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

5 10 15 20 25 300Time (h)

ndash25

ndash20

ndash15

ndash10

ndash5

0

5

10

15

Tem

pera

ture

(degC)

Figure 4 Variations in the tunnel air temperature over time

6 Advances in Civil Engineering

and amplitude of the surrounding rock temperature arerelated to the depth of the tunnel surrounding rock thegroundwater seepage velocity and the wind speed -ecooling rate and amplitude of the surrounding rock tem-perature at the TS9 monitoring point are the largest andthose at the TS11 monitoring point are the smallest -usthe deeper the tunnel surrounding rock is the lower thecooling rate and amplitude of the tunnel surrounding rocktemperature are Lower groundwater seepage velocities andhigher wind speeds lead to greater cooling rates and am-plitudes of the surrounding rock temperature -e influenceof groundwater seepage and tunnel ventilation on thesurrounding rock temperature field is related to the depth ofthe surrounding rock -e increase in wind speed has astrong influence on the temperature field at TS9 and TS10but a weak influence on that at TS11 Figure 6 also shows thatthe wind speed has the most significant influence on thesurrounding rock temperature field when the groundwaterseepage velocity is 0923md but has the least significantinfluence on the surrounding rock temperature field whenthe groundwater seepage velocity is 0md -is can beexplained by the coupling effect of groundwater seepage andtunnel ventilation

Figure 7 presents the variations in the surrounding rocktemperature drops under groundwater seepage velocities atdifferent wind speeds after 115h of cooling It also shows thatthe temperature drops in the tunnel surrounding rock decreaseas the groundwater seepage velocity increases -e temperaturedrops differ at TS9 TS10 and TS11 under different windspeeds -e temperature drop at TS11 at different wind speedsdecreases linearly as the groundwater seepage velocity increasesAt wind speeds of 0606ms and 1002ms the temperaturedrops at TS9 and TS10 decrease linearly as the groundwaterseepage velocity increases At a wind speed of 2398ms andgroundwater seepage velocity under 0923md the temperaturedrops at TS9 and TS10 slowly decrease as the groundwater

seepage velocity increases At a wind speed of 2398ms andgroundwater seepage velocity over 0923md the temperaturedrops at TS9 and TS10 sharply decrease as the groundwaterseepage velocity increases

-e above analysis shows that groundwater seepage andtunnel ventilation have a coupling effect on the surroundingrock temperature Specifically higher groundwater seepagevelocities and lower wind speeds lead to higher surroundingrock temperatures -us the coupling influence ofgroundwater seepage and tunnel ventilation should beconsidered when designing the insulation layers of coldregion tunnels

33 Effect of Groundwater Seepage on the Temperature at theInterface between the Lining and Surrounding RockFigure 8 presents the temperature variation over time at theinterface between the lining and surrounding rock under theinfluence of groundwater seepage and ventilation in themodel test It shows that the interface temperatures of TS1TS3 TS4 TS5 and TS6 decrease over time when ground-water seepage and ventilation are considered in the modeltest Groundwater seepage has a significant effect on theinterface temperature -e effect is related to the location ofthe monitoring points -erefore the cooling rates andamplitudes of the interface temperature for TS1 TS3 TS4TS5 and TS6 differ significantly -e groundwater seepagehas the most significant effects on measuring points TS3 andTS4 and has the least significant effects on measuring pointsTS1 and TS6 Wind speed also has a significant effect on theinterface temperature -e effect is related to the ground-water seepage velocity -ese results indicate that ground-water seepage and tunnel ventilation have a coupling effecton the interface temperature and that this coupling effect isrelated to the interface location

Figure 9 shows the variations in the temperature drops atTS1 TS3 TS4 TS5 and TS6 with groundwater seepagevelocity under tunnel ventilation after 115 h of cooling Itshows that the temperature drops at TS3 and TS4 upstreamof the groundwater seepage field decrease as the ground-water seepage velocity increases However the temperaturedrops at TS1 and TS6 downstream of the groundwaterseepage field increase as the groundwater seepage velocityincreases from 0 to 0923md Furthermore the temperaturedrops at TS1 and TS6 decrease as the groundwater seepagevelocity increases from 0923 to 2743md -e smallesttemperature drop occurs at TS3 (upstream of the ground-water seepage field) and the largest temperature drop occursat TS1 (downstream of the groundwater seepage field) undergroundwater seepage -ese results indicate that ground-water seepage leads to an uneven temperature distribution atthe interface between the lining and surrounding rock andthat tunnel ventilation enhances this uneven distribution

Figure 10 presents the temperature differences betweenTS3TS5 and TS6 -e temperature at TS3 is higher undergroundwater seepage than those at TS5 and TS6 -e interfacetemperature upstream of the groundwater field is higher thanthat downstream Figure 10 also shows that the temperaturedifference between TS3 and TS6 increases as the groundwater

Wind speed = 0606msWind speed = 1002msWind speed = 2389ms

Groundwater seepage

TA 18cm

ndash22

ndash21

ndash20

ndash19

ndash18

ndash17

ndash16

ndash15

Tem

pera

ture

(degC)

05 10 15 20 25 3000Groundwater seepage velocity (md)

Figure 5 Variations in the tunnel air temperature after 115 h ofcooling

Advances in Civil Engineering 7

Deicing of refrigerator Deicing of refrigerator

0 5 10 15 20 25 30Time (h)

0

2

4

6

8

10

12

14Te

mpe

ratu

re (deg

C)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(a)

Deicing of refrigeratorDeicing of refrigerator

0

2

4

6

8

10

12

14

Tem

pera

ture

(degC)

5 10 15 20 25 300Time (h)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(b)

Deicing of refrigerator

Groundwater seepage

TA TS9

1cm4cm 5cm

TS10 TS1118cm

Deicing of refrigerator

0

2

4

6

8

10

12

Tem

pera

ture

(degC)

5 10 15 20 25 300Time (h)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(c)

Figure 6 Variations in the surrounding rock temperature over time

8 Advances in Civil Engineering

seepage velocity increases -us the higher the groundwaterseepage velocity is the higher the temperature difference isbetween TS3 and TS6-e temperature difference between TS3and TS5 increases as the groundwater seepage velocity increasesfrom 0 to 0923md and decreases as the groundwater seepagevelocity increases from 0923 to 2743md Groundwaterseepage has a great effect on the interface temperature -iseffect has a spatial difference -us both the shape and size ofthe cross section of the tunnel significantly affect the interfacetemperature under groundwater seepage

34 Effect of Groundwater Seepage on the Freezing Damage toCold Region Tunnels -e tunnel drainage system is lo-cated between the lining and the surrounding rock

Monitoring points TS3 TS5 and TS6 are located at thetop middle and foot of the tunnel drainage systemrespectively -e temperatures at TS3 TS5 and TS6determine the antifreezing ability of cold region tunnels-erefore the higher the temperatures at TS3 TS5 andTS6 are the stronger the antifreezing capability of thetunnel in cold regions is Figure 8 shows that when thegroundwater seepage velocity is 0 md the measuringpoints TS3 TS5 and TS6 freeze synchronously If thetunnel surrounding rock is free of frost heaving coldregion tunnels may not need a thermal insulation layerWhen the groundwater seepage velocity is 0923 md themonitoring point TS6 freezes first -e interface thengradually freezes from TS6 to TS5 along the circumfer-ential direction of the tunnel section -is explains why

Tem

pera

ture

dro

p (deg

C)

Groundwater seepage

TS9TS10TS11

0

2

4

6

8

10

12

05 10 15 20 25 3000

18cm TA TS9 TS104cm

1cm5cm

TS11

Groundwater seepage velocity (md)

(a)

Tem

pera

ture

dro

p (deg

C)

TS9TS10TS11

Groundwater seepage

18cm TA TS9 TS104cm

1cm5cm

TS11

0

2

4

6

8

10

12

05 10 15 20 25 3000Groundwater seepage velocity (md)

(b)

Tem

pera

ture

dro

p (deg

C)

TS9TS10TS11

Groundwater seepage

18cm TA TS9 TS104cm

1cm5cm

TS11

0

2

4

6

8

10

12

05 10 15 20 25 3000Groundwater seepage velocity (md)

(c)

Figure 7 Variations in the surrounding rock temperature drop at different groundwater seepage velocities after 115 h of cooling Averagewind speed of (a) 0606ms (b) 1002ms and (c) 2398ms

Advances in Civil Engineering 9

ndash202468

101214

ndash202468

1012

Deicing of refrigeratorDeicing of refrigerator0degC

Deicing of refrigeratorDeicing of refrigerator

Deicing of refrigerator

0degC

Tem

pera

ture

(degC)

Tem

pera

ture

(degC)

ndash202468

101214

ndash202468

1012

Tem

pera

ture

(degC)

Tem

pera

ture

(degC)

Deicing of refrigerator Deicing of refrigerator

0degC 0degC

Deicing of refrigerator

0 5 10 15 20 25 30 0 5 10 15 20 25 30Time (h) Time (h)

0 5 10 15 20 25 30 0 5 10 15 20 25 30Time (h) Time (h)

(e)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(c) (d)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(a) (b)

ndash202468

1012

Tem

pera

ture

(degC)

ndash202468

1012

Tem

pera

ture

(degC)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Groundwater seepage

Deicing of refrigerator Deicing of refrigerator

0degC

0 5 10 15 20 25 30 0 5 10 15 20 25 30Time (h) Time (h)

TS1

TS6

TS5

TS4

TS3

18cmTA45deg

45deg

Figure 8 Variations in the temperature at the interface between the lining and the surrounding rock (a) TS1 (b) TS3 (c) TS4 (d) TS5 and(e) TS6

10 Advances in Civil Engineering

cold region tunnels suffer tunnel lining leakage and roadicing -e results of the model test reveal the cause oftunnel lining leakage and road icing To avoid tunnelleakage in cold region tunnels a thermal insulation layershould be properly designed and a heating device shouldbe installed in its longitudinal drainage pipe when thegroundwater seepage velocity is low When thegroundwater seepage velocity is 2743md the moni-toring point at TS6 freezes but the monitoring points atTS3 and TS5 do not Furthermore their temperatures do

not decrease significantly as cooling time increases-erefore the tunnel has good antifreezing capabilitywhen the groundwater seepage velocity is high -is goodantifreezing capability should be fully utilized Further-more the foot of the tunnel drainage system should bestrengthened against freezing via an insulation layer andheating device

-e above analysis demonstrates that cold region tunnelshave an antifreezing capability that is mainly related to the frostheaving of the surrounding rock and the groundwater seepage

Groundwater seepage

TS1TS3TS4

TS5TS6

Tem

pera

ture

dro

p (deg

C)

TA

TS3TS4

TS5

TS6TS1

45deg45deg

18cm

2

4

6

8

10

12

14

05 10 15 20 25 3000Groundwater seepage velocity (md)

(a)

TS1TS3TS4

TS5TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3TS4

TS5

TS6TS1

45deg45deg

18cm

2

4

6

8

10

12

14

05 10 15 20 25 3000Groundwater seepage velocity (md)

(b)

TS1TS3TS4

TS5TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3TS4

TS5

TS6TS1

45deg45deg

18cm

2

4

6

8

10

12

14

05 10 15 20 25 3000Groundwater seepage velocity (md)

(c)

Figure 9 Variations in the surrounding rock temperature drop at different groundwater seepage velocities after 115 h of cooling Averagewind speed of (a) 0606ms (b) 1002ms and (c) 2398ms

Advances in Civil Engineering 11

velocity -is antifreezing capability should be fully utilized inthe antifreezing design of cold region tunnels

4 Conclusions

A systematic study on the temperature field of cold regiontunnels is presented in which a model test that considers thecoupling effects of groundwater seepage and tunnel venti-lation is conducted -e effects of groundwater seepage onthe air temperature in the tunnel the surrounding rocktemperature the temperature at the interface between thelining and surrounding rock and the freezing damage of thetunnel in cold regions are studied -e following four mainconclusions are drawn

First groundwater seepage has a significant effect on theair temperature in the tunnel -e higher the groundwater

seepage velocity the higher the air temperature in thetunnel Groundwater seepage has a significant influence onthe thickness and length of the tunnel insulation layer in coldregions -e thickness and length of the tunnel insulationlayer can decrease under groundwater seepage

Second groundwater seepage and tunnel ventilationhave a coupling effect on the surrounding rock temperatureHigher groundwater seepage velocity and lower wind speedlead to higher surrounding rock temperature -e influenceof groundwater seepage and tunnel ventilation on thesurrounding rock temperature field is related to the depth ofthe surrounding rock

-ird groundwater seepage leads to an uneven tem-perature distribution at the interface between the lining andsurrounding rock -e tunnel ventilation further enhancesthis uneven temperature distribution -e groundwater

TS3-TS5TS3-TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3

TS5

TS6

45deg 18cm

ndash1

0

1

2

3

4

5

6

7

8

9

05 10 15 20 25 3000Groundwater seepage velocity (md)

(a)

TS3-TS5TS3-TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3

TS5

TS6

45deg 18cm

ndash1

0

1

2

3

4

5

6

7

8

9

05 10 15 20 25 3000Groundwater seepage velocity (md)

(b)

TS3-TS5TS3-TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3

TS5

TS6

45deg 18cm

ndash1

0

1

2

3

4

5

6

7

8

9

05 10 15 20 25 3000Groundwater seepage velocity (md)

(c)

Figure 10 Relationships between the temperature differences at TS5 TS6 and TS3 and groundwater seepage velocity Average wind speedof (a) 0606ms (b) 1002ms and (c) 2398ms

12 Advances in Civil Engineering

seepage and tunnel ventilation have a coupling effect on theinterface temperature -is coupling effect is related to theinterface location -e influence of the groundwater seepagevelocity on the interface temperature has a spatial difference-e shape and size of the cross section of the tunnel have asignificant influence on the interface temperature undergroundwater seepage

Fourth cold region tunnels have an antifreezing capa-bility that is mainly related to the frost heaving of thesurrounding rock and the groundwater seepage velocity-eantifreezing capability of the tunnel should be fully utilizedin the antifreezing design of cold region tunnels

Data Availability

-e data used to support the findings of this study areavailable from the corresponding author upon request

Conflicts of Interest

-e authors declare that they have no conflicts of interest

Acknowledgments

-is study was supported by the Key Laboratory of Geo-technical and Underground Engineering of Ministry ofEducation Tongji University (No KLE-TJGE-B1605) theKey Laboratory of Rock Mechanics and Geohazards ofZhejiang Province (No ZJRM-2018-Y-01) and the SichuanScience and Technology Program (No 2018GZ0359)

References

[1] S Li M Zhang W Pei and Y Lai ldquoExperimental and nu-merical simulations on heat-water-mechanics interactionmechanism in a freezing soilrdquo Applied =ermal Engineeringvol 132 pp 209ndash220 2018

[2] S Li M Zhang Y Tian W Pei and H Zhong ldquoExperimentaland numerical investigations on frost damage mechanism of acanal in cold regionsrdquo Cold Regions Science and Technologyvol 116 pp 1ndash11 2015

[3] S Shen C Xia J Huang and Y Li ldquoInfluence of seasonal meltlayer depth on the stability of surrounding rock in permafrostregions based on the measurementrdquoNatural Hazards vol 75no 3 pp 2545ndash2557 2015

[4] K-J Jun Y-C Hwang and C-Y Yune ldquoField measurementof temperature inside tunnel in winter in Gangwon KoreardquoCold Regions Science and Technology vol 143 pp 32ndash42 2017

[5] Q Ma X Luo Y Lai F Niu and J Gao ldquoNumerical in-vestigation on thermal insulation layer of a tunnel in sea-sonally frozen regionsrdquoApplied=ermal Engineering vol 138pp 280ndash291 2018

[6] X Zhao X Yang H Zhang H Lai and X Wang ldquoAnanalytical solution for frost heave force by the multifactor ofcoupled heat and moisture transfer in cold-region tunnelsrdquoCold Regions Science and Technology vol 175 2020

[7] Y M Lai S Y Liu Z W Wu and W Yu ldquoApproximateanalytical solution for temperature fields in cold regionscircular tunnelsrdquoCold Regions Science and Technology vol 34no 1 pp 43ndash49 2002

[8] G Zhang C Xia M Sun Y Zou and S Xiao ldquoA new modeland analytical solution for the heat conduction of tunnel

lining ground heat exchangersrdquo Cold Regions Science andTechnology vol 88 pp 59ndash66 2013

[9] Y M Lai Z W Wu Y L Zhu and L N Zhu ldquoNonlinearanalysis for the coupled problem of temperature seepage andstress fields in cold-region tunnelsrdquo Tunnelling and Under-ground Space Technology vol 13 no 4 pp 435ndash440 1998

[10] X Zhang J Xiao Y Zhang et al ldquoStudy of the function of theinsulation layer for treating water leakage in permafrosttunnelsrdquo Applied =ermal Engineering vol 27 no 2-3pp 637ndash645 2007

[11] X Zhang Y Lai W Yu and S Zhang ldquoNon-linear analysisfor the freezing-thawing situation of the rock surrounding thetunnel in cold regions under the conditions of differentconstruction seasons initial temperatures and insulationsrdquoTunnelling and Underground Space Technology vol 17 no 3pp 315ndash325 2002

[12] X Zhang Y Lai W Yu and Y Wu ldquoForecast analysis for there-frozen of Feng Huoshan permafrost tunnel on Qing-Zangrailwayrdquo Tunnelling and Underground Space Technologyvol 19 no 1 pp 45ndash56 2004

[13] X Tan W Chen H Tian and J Cao ldquoWater flow and heattransport including icewater phase change in porous medianumerical simulation and applicationrdquo Cold Regions Scienceand Technology vol 68 no 1-2 pp 74ndash84 2011

[14] X Tan W Chen G Wu and J Yang ldquoNumerical simulationsof heat transfer with ice-water phase change occurring inporous media and application to a cold-region tunnelrdquoTunnelling and Underground Space Technology vol 38pp 170ndash179 2013

[15] X Tan W Chen D Yang et al ldquoStudy on the influence ofairflow on the temperature of the surrounding rock in a coldregion tunnel and its application to insulation layer designrdquoApplied =ermal Engineering vol 67 no 1-2 pp 320ndash3342014

[16] S Li F Niu Y Lai W Pei and W Yu ldquoOptimal design ofthermal insulation layer of a tunnel in permafrost regionsbased on coupled heat-water simulationrdquo Applied =ermalEngineering vol 110 pp 1264ndash1273 2017

[17] Q Yan B Li Y Zhang J Yan and C Zhang ldquoNumericalinvestigation of heat-insulating layers in a cold region tunneltaking into account airflow and heat transferrdquo Applied Sci-ences vol 7 no 7 p 679 2017

[18] Q Feng B-S Jiang Q Zhang and G Wang ldquoReliabilityresearch on the 5-cm-thick insulation layer used in theYuximolegai tunnel based on a physical model testrdquo ColdRegions Science and Technology vol 124 pp 54ndash66 2016

[19] X Zhang Z Zhou J Li Y Zhou and F Han ldquoA physicalmodel experiment for investigating into temperature redis-tribution in surrounding rock of permafrost tunnelrdquo ColdRegions Science and Technology vol 151 pp 47ndash52 2018

[20] Y Zeng K Liu X Zhou and L Fan ldquoTunnel temperaturefields analysis under the couple effect of convection-con-duction in cold regionsrdquo Applied =ermal Engineeringvol 120 pp 378ndash392 2017

[21] L Liu Z Li X Liu and Y Li ldquoFrost front research of a cold-region tunnel considering ventilation based on a physicalmodel testrdquo Tunnelling and Underground Space Technologyvol 77 pp 261ndash279 2018

[22] G Zhang Y Guo Y Zhou et al ldquoExperimental study on thethermal performance of tunnel lining GHE under ground-water flowrdquo Applied =ermal Engineering vol 106 pp 784ndash795 2016

[23] G Zhang S Liu X Zhao et al ldquo-e coupling effect ofventilation and groundwater flow on the thermal performance

Advances in Civil Engineering 13

of tunnel lining GHEsrdquoApplied=ermal Engineering vol 112pp 595ndash605 2017

[24] Q Hu R Shi Y Hu et al ldquoMethod to evaluate the safety oftunnels through steeply inclined strata in cold regions basedon the sidewall frost heave modelrdquo Journal of Performance ofConstructed Facilities vol 32 2018

[25] H Cai P Li and Z Wu ldquoModel test of liquid nitrogenfreezing-temperature field of improved plastic freezing piperdquoJournal of Cold Regions Engineering vol 34 no 1 2020

[26] S E A Gehlin and G Hellstrom ldquoInfluence on thermalresponse test by groundwater flow in vertical fractures in hardrockrdquo Renewable Energy vol 28 no 14 pp 2221ndash2238 2003

14 Advances in Civil Engineering

and amplitude of the surrounding rock temperature arerelated to the depth of the tunnel surrounding rock thegroundwater seepage velocity and the wind speed -ecooling rate and amplitude of the surrounding rock tem-perature at the TS9 monitoring point are the largest andthose at the TS11 monitoring point are the smallest -usthe deeper the tunnel surrounding rock is the lower thecooling rate and amplitude of the tunnel surrounding rocktemperature are Lower groundwater seepage velocities andhigher wind speeds lead to greater cooling rates and am-plitudes of the surrounding rock temperature -e influenceof groundwater seepage and tunnel ventilation on thesurrounding rock temperature field is related to the depth ofthe surrounding rock -e increase in wind speed has astrong influence on the temperature field at TS9 and TS10but a weak influence on that at TS11 Figure 6 also shows thatthe wind speed has the most significant influence on thesurrounding rock temperature field when the groundwaterseepage velocity is 0923md but has the least significantinfluence on the surrounding rock temperature field whenthe groundwater seepage velocity is 0md -is can beexplained by the coupling effect of groundwater seepage andtunnel ventilation

Figure 7 presents the variations in the surrounding rocktemperature drops under groundwater seepage velocities atdifferent wind speeds after 115h of cooling It also shows thatthe temperature drops in the tunnel surrounding rock decreaseas the groundwater seepage velocity increases -e temperaturedrops differ at TS9 TS10 and TS11 under different windspeeds -e temperature drop at TS11 at different wind speedsdecreases linearly as the groundwater seepage velocity increasesAt wind speeds of 0606ms and 1002ms the temperaturedrops at TS9 and TS10 decrease linearly as the groundwaterseepage velocity increases At a wind speed of 2398ms andgroundwater seepage velocity under 0923md the temperaturedrops at TS9 and TS10 slowly decrease as the groundwater

seepage velocity increases At a wind speed of 2398ms andgroundwater seepage velocity over 0923md the temperaturedrops at TS9 and TS10 sharply decrease as the groundwaterseepage velocity increases

-e above analysis shows that groundwater seepage andtunnel ventilation have a coupling effect on the surroundingrock temperature Specifically higher groundwater seepagevelocities and lower wind speeds lead to higher surroundingrock temperatures -us the coupling influence ofgroundwater seepage and tunnel ventilation should beconsidered when designing the insulation layers of coldregion tunnels

33 Effect of Groundwater Seepage on the Temperature at theInterface between the Lining and Surrounding RockFigure 8 presents the temperature variation over time at theinterface between the lining and surrounding rock under theinfluence of groundwater seepage and ventilation in themodel test It shows that the interface temperatures of TS1TS3 TS4 TS5 and TS6 decrease over time when ground-water seepage and ventilation are considered in the modeltest Groundwater seepage has a significant effect on theinterface temperature -e effect is related to the location ofthe monitoring points -erefore the cooling rates andamplitudes of the interface temperature for TS1 TS3 TS4TS5 and TS6 differ significantly -e groundwater seepagehas the most significant effects on measuring points TS3 andTS4 and has the least significant effects on measuring pointsTS1 and TS6 Wind speed also has a significant effect on theinterface temperature -e effect is related to the ground-water seepage velocity -ese results indicate that ground-water seepage and tunnel ventilation have a coupling effecton the interface temperature and that this coupling effect isrelated to the interface location

Figure 9 shows the variations in the temperature drops atTS1 TS3 TS4 TS5 and TS6 with groundwater seepagevelocity under tunnel ventilation after 115 h of cooling Itshows that the temperature drops at TS3 and TS4 upstreamof the groundwater seepage field decrease as the ground-water seepage velocity increases However the temperaturedrops at TS1 and TS6 downstream of the groundwaterseepage field increase as the groundwater seepage velocityincreases from 0 to 0923md Furthermore the temperaturedrops at TS1 and TS6 decrease as the groundwater seepagevelocity increases from 0923 to 2743md -e smallesttemperature drop occurs at TS3 (upstream of the ground-water seepage field) and the largest temperature drop occursat TS1 (downstream of the groundwater seepage field) undergroundwater seepage -ese results indicate that ground-water seepage leads to an uneven temperature distribution atthe interface between the lining and surrounding rock andthat tunnel ventilation enhances this uneven distribution

Figure 10 presents the temperature differences betweenTS3TS5 and TS6 -e temperature at TS3 is higher undergroundwater seepage than those at TS5 and TS6 -e interfacetemperature upstream of the groundwater field is higher thanthat downstream Figure 10 also shows that the temperaturedifference between TS3 and TS6 increases as the groundwater

Wind speed = 0606msWind speed = 1002msWind speed = 2389ms

Groundwater seepage

TA 18cm

ndash22

ndash21

ndash20

ndash19

ndash18

ndash17

ndash16

ndash15

Tem

pera

ture

(degC)

05 10 15 20 25 3000Groundwater seepage velocity (md)

Figure 5 Variations in the tunnel air temperature after 115 h ofcooling

Advances in Civil Engineering 7

Deicing of refrigerator Deicing of refrigerator

0 5 10 15 20 25 30Time (h)

0

2

4

6

8

10

12

14Te

mpe

ratu

re (deg

C)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(a)

Deicing of refrigeratorDeicing of refrigerator

0

2

4

6

8

10

12

14

Tem

pera

ture

(degC)

5 10 15 20 25 300Time (h)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(b)

Deicing of refrigerator

Groundwater seepage

TA TS9

1cm4cm 5cm

TS10 TS1118cm

Deicing of refrigerator

0

2

4

6

8

10

12

Tem

pera

ture

(degC)

5 10 15 20 25 300Time (h)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(c)

Figure 6 Variations in the surrounding rock temperature over time

8 Advances in Civil Engineering

seepage velocity increases -us the higher the groundwaterseepage velocity is the higher the temperature difference isbetween TS3 and TS6-e temperature difference between TS3and TS5 increases as the groundwater seepage velocity increasesfrom 0 to 0923md and decreases as the groundwater seepagevelocity increases from 0923 to 2743md Groundwaterseepage has a great effect on the interface temperature -iseffect has a spatial difference -us both the shape and size ofthe cross section of the tunnel significantly affect the interfacetemperature under groundwater seepage

34 Effect of Groundwater Seepage on the Freezing Damage toCold Region Tunnels -e tunnel drainage system is lo-cated between the lining and the surrounding rock

Monitoring points TS3 TS5 and TS6 are located at thetop middle and foot of the tunnel drainage systemrespectively -e temperatures at TS3 TS5 and TS6determine the antifreezing ability of cold region tunnels-erefore the higher the temperatures at TS3 TS5 andTS6 are the stronger the antifreezing capability of thetunnel in cold regions is Figure 8 shows that when thegroundwater seepage velocity is 0 md the measuringpoints TS3 TS5 and TS6 freeze synchronously If thetunnel surrounding rock is free of frost heaving coldregion tunnels may not need a thermal insulation layerWhen the groundwater seepage velocity is 0923 md themonitoring point TS6 freezes first -e interface thengradually freezes from TS6 to TS5 along the circumfer-ential direction of the tunnel section -is explains why

Tem

pera

ture

dro

p (deg

C)

Groundwater seepage

TS9TS10TS11

0

2

4

6

8

10

12

05 10 15 20 25 3000

18cm TA TS9 TS104cm

1cm5cm

TS11

Groundwater seepage velocity (md)

(a)

Tem

pera

ture

dro

p (deg

C)

TS9TS10TS11

Groundwater seepage

18cm TA TS9 TS104cm

1cm5cm

TS11

0

2

4

6

8

10

12

05 10 15 20 25 3000Groundwater seepage velocity (md)

(b)

Tem

pera

ture

dro

p (deg

C)

TS9TS10TS11

Groundwater seepage

18cm TA TS9 TS104cm

1cm5cm

TS11

0

2

4

6

8

10

12

05 10 15 20 25 3000Groundwater seepage velocity (md)

(c)

Figure 7 Variations in the surrounding rock temperature drop at different groundwater seepage velocities after 115 h of cooling Averagewind speed of (a) 0606ms (b) 1002ms and (c) 2398ms

Advances in Civil Engineering 9

ndash202468

101214

ndash202468

1012

Deicing of refrigeratorDeicing of refrigerator0degC

Deicing of refrigeratorDeicing of refrigerator

Deicing of refrigerator

0degC

Tem

pera

ture

(degC)

Tem

pera

ture

(degC)

ndash202468

101214

ndash202468

1012

Tem

pera

ture

(degC)

Tem

pera

ture

(degC)

Deicing of refrigerator Deicing of refrigerator

0degC 0degC

Deicing of refrigerator

0 5 10 15 20 25 30 0 5 10 15 20 25 30Time (h) Time (h)

0 5 10 15 20 25 30 0 5 10 15 20 25 30Time (h) Time (h)

(e)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(c) (d)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(a) (b)

ndash202468

1012

Tem

pera

ture

(degC)

ndash202468

1012

Tem

pera

ture

(degC)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Groundwater seepage

Deicing of refrigerator Deicing of refrigerator

0degC

0 5 10 15 20 25 30 0 5 10 15 20 25 30Time (h) Time (h)

TS1

TS6

TS5

TS4

TS3

18cmTA45deg

45deg

Figure 8 Variations in the temperature at the interface between the lining and the surrounding rock (a) TS1 (b) TS3 (c) TS4 (d) TS5 and(e) TS6

10 Advances in Civil Engineering

cold region tunnels suffer tunnel lining leakage and roadicing -e results of the model test reveal the cause oftunnel lining leakage and road icing To avoid tunnelleakage in cold region tunnels a thermal insulation layershould be properly designed and a heating device shouldbe installed in its longitudinal drainage pipe when thegroundwater seepage velocity is low When thegroundwater seepage velocity is 2743md the moni-toring point at TS6 freezes but the monitoring points atTS3 and TS5 do not Furthermore their temperatures do

not decrease significantly as cooling time increases-erefore the tunnel has good antifreezing capabilitywhen the groundwater seepage velocity is high -is goodantifreezing capability should be fully utilized Further-more the foot of the tunnel drainage system should bestrengthened against freezing via an insulation layer andheating device

-e above analysis demonstrates that cold region tunnelshave an antifreezing capability that is mainly related to the frostheaving of the surrounding rock and the groundwater seepage

Groundwater seepage

TS1TS3TS4

TS5TS6

Tem

pera

ture

dro

p (deg

C)

TA

TS3TS4

TS5

TS6TS1

45deg45deg

18cm

2

4

6

8

10

12

14

05 10 15 20 25 3000Groundwater seepage velocity (md)

(a)

TS1TS3TS4

TS5TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3TS4

TS5

TS6TS1

45deg45deg

18cm

2

4

6

8

10

12

14

05 10 15 20 25 3000Groundwater seepage velocity (md)

(b)

TS1TS3TS4

TS5TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3TS4

TS5

TS6TS1

45deg45deg

18cm

2

4

6

8

10

12

14

05 10 15 20 25 3000Groundwater seepage velocity (md)

(c)

Figure 9 Variations in the surrounding rock temperature drop at different groundwater seepage velocities after 115 h of cooling Averagewind speed of (a) 0606ms (b) 1002ms and (c) 2398ms

Advances in Civil Engineering 11

velocity -is antifreezing capability should be fully utilized inthe antifreezing design of cold region tunnels

4 Conclusions

A systematic study on the temperature field of cold regiontunnels is presented in which a model test that considers thecoupling effects of groundwater seepage and tunnel venti-lation is conducted -e effects of groundwater seepage onthe air temperature in the tunnel the surrounding rocktemperature the temperature at the interface between thelining and surrounding rock and the freezing damage of thetunnel in cold regions are studied -e following four mainconclusions are drawn

First groundwater seepage has a significant effect on theair temperature in the tunnel -e higher the groundwater

seepage velocity the higher the air temperature in thetunnel Groundwater seepage has a significant influence onthe thickness and length of the tunnel insulation layer in coldregions -e thickness and length of the tunnel insulationlayer can decrease under groundwater seepage

Second groundwater seepage and tunnel ventilationhave a coupling effect on the surrounding rock temperatureHigher groundwater seepage velocity and lower wind speedlead to higher surrounding rock temperature -e influenceof groundwater seepage and tunnel ventilation on thesurrounding rock temperature field is related to the depth ofthe surrounding rock

-ird groundwater seepage leads to an uneven tem-perature distribution at the interface between the lining andsurrounding rock -e tunnel ventilation further enhancesthis uneven temperature distribution -e groundwater

TS3-TS5TS3-TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3

TS5

TS6

45deg 18cm

ndash1

0

1

2

3

4

5

6

7

8

9

05 10 15 20 25 3000Groundwater seepage velocity (md)

(a)

TS3-TS5TS3-TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3

TS5

TS6

45deg 18cm

ndash1

0

1

2

3

4

5

6

7

8

9

05 10 15 20 25 3000Groundwater seepage velocity (md)

(b)

TS3-TS5TS3-TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3

TS5

TS6

45deg 18cm

ndash1

0

1

2

3

4

5

6

7

8

9

05 10 15 20 25 3000Groundwater seepage velocity (md)

(c)

Figure 10 Relationships between the temperature differences at TS5 TS6 and TS3 and groundwater seepage velocity Average wind speedof (a) 0606ms (b) 1002ms and (c) 2398ms

12 Advances in Civil Engineering

seepage and tunnel ventilation have a coupling effect on theinterface temperature -is coupling effect is related to theinterface location -e influence of the groundwater seepagevelocity on the interface temperature has a spatial difference-e shape and size of the cross section of the tunnel have asignificant influence on the interface temperature undergroundwater seepage

Fourth cold region tunnels have an antifreezing capa-bility that is mainly related to the frost heaving of thesurrounding rock and the groundwater seepage velocity-eantifreezing capability of the tunnel should be fully utilizedin the antifreezing design of cold region tunnels

Data Availability

-e data used to support the findings of this study areavailable from the corresponding author upon request

Conflicts of Interest

-e authors declare that they have no conflicts of interest

Acknowledgments

-is study was supported by the Key Laboratory of Geo-technical and Underground Engineering of Ministry ofEducation Tongji University (No KLE-TJGE-B1605) theKey Laboratory of Rock Mechanics and Geohazards ofZhejiang Province (No ZJRM-2018-Y-01) and the SichuanScience and Technology Program (No 2018GZ0359)

References

[1] S Li M Zhang W Pei and Y Lai ldquoExperimental and nu-merical simulations on heat-water-mechanics interactionmechanism in a freezing soilrdquo Applied =ermal Engineeringvol 132 pp 209ndash220 2018

[2] S Li M Zhang Y Tian W Pei and H Zhong ldquoExperimentaland numerical investigations on frost damage mechanism of acanal in cold regionsrdquo Cold Regions Science and Technologyvol 116 pp 1ndash11 2015

[3] S Shen C Xia J Huang and Y Li ldquoInfluence of seasonal meltlayer depth on the stability of surrounding rock in permafrostregions based on the measurementrdquoNatural Hazards vol 75no 3 pp 2545ndash2557 2015

[4] K-J Jun Y-C Hwang and C-Y Yune ldquoField measurementof temperature inside tunnel in winter in Gangwon KoreardquoCold Regions Science and Technology vol 143 pp 32ndash42 2017

[5] Q Ma X Luo Y Lai F Niu and J Gao ldquoNumerical in-vestigation on thermal insulation layer of a tunnel in sea-sonally frozen regionsrdquoApplied=ermal Engineering vol 138pp 280ndash291 2018

[6] X Zhao X Yang H Zhang H Lai and X Wang ldquoAnanalytical solution for frost heave force by the multifactor ofcoupled heat and moisture transfer in cold-region tunnelsrdquoCold Regions Science and Technology vol 175 2020

[7] Y M Lai S Y Liu Z W Wu and W Yu ldquoApproximateanalytical solution for temperature fields in cold regionscircular tunnelsrdquoCold Regions Science and Technology vol 34no 1 pp 43ndash49 2002

[8] G Zhang C Xia M Sun Y Zou and S Xiao ldquoA new modeland analytical solution for the heat conduction of tunnel

lining ground heat exchangersrdquo Cold Regions Science andTechnology vol 88 pp 59ndash66 2013

[9] Y M Lai Z W Wu Y L Zhu and L N Zhu ldquoNonlinearanalysis for the coupled problem of temperature seepage andstress fields in cold-region tunnelsrdquo Tunnelling and Under-ground Space Technology vol 13 no 4 pp 435ndash440 1998

[10] X Zhang J Xiao Y Zhang et al ldquoStudy of the function of theinsulation layer for treating water leakage in permafrosttunnelsrdquo Applied =ermal Engineering vol 27 no 2-3pp 637ndash645 2007

[11] X Zhang Y Lai W Yu and S Zhang ldquoNon-linear analysisfor the freezing-thawing situation of the rock surrounding thetunnel in cold regions under the conditions of differentconstruction seasons initial temperatures and insulationsrdquoTunnelling and Underground Space Technology vol 17 no 3pp 315ndash325 2002

[12] X Zhang Y Lai W Yu and Y Wu ldquoForecast analysis for there-frozen of Feng Huoshan permafrost tunnel on Qing-Zangrailwayrdquo Tunnelling and Underground Space Technologyvol 19 no 1 pp 45ndash56 2004

[13] X Tan W Chen H Tian and J Cao ldquoWater flow and heattransport including icewater phase change in porous medianumerical simulation and applicationrdquo Cold Regions Scienceand Technology vol 68 no 1-2 pp 74ndash84 2011

[14] X Tan W Chen G Wu and J Yang ldquoNumerical simulationsof heat transfer with ice-water phase change occurring inporous media and application to a cold-region tunnelrdquoTunnelling and Underground Space Technology vol 38pp 170ndash179 2013

[15] X Tan W Chen D Yang et al ldquoStudy on the influence ofairflow on the temperature of the surrounding rock in a coldregion tunnel and its application to insulation layer designrdquoApplied =ermal Engineering vol 67 no 1-2 pp 320ndash3342014

[16] S Li F Niu Y Lai W Pei and W Yu ldquoOptimal design ofthermal insulation layer of a tunnel in permafrost regionsbased on coupled heat-water simulationrdquo Applied =ermalEngineering vol 110 pp 1264ndash1273 2017

[17] Q Yan B Li Y Zhang J Yan and C Zhang ldquoNumericalinvestigation of heat-insulating layers in a cold region tunneltaking into account airflow and heat transferrdquo Applied Sci-ences vol 7 no 7 p 679 2017

[18] Q Feng B-S Jiang Q Zhang and G Wang ldquoReliabilityresearch on the 5-cm-thick insulation layer used in theYuximolegai tunnel based on a physical model testrdquo ColdRegions Science and Technology vol 124 pp 54ndash66 2016

[19] X Zhang Z Zhou J Li Y Zhou and F Han ldquoA physicalmodel experiment for investigating into temperature redis-tribution in surrounding rock of permafrost tunnelrdquo ColdRegions Science and Technology vol 151 pp 47ndash52 2018

[20] Y Zeng K Liu X Zhou and L Fan ldquoTunnel temperaturefields analysis under the couple effect of convection-con-duction in cold regionsrdquo Applied =ermal Engineeringvol 120 pp 378ndash392 2017

[21] L Liu Z Li X Liu and Y Li ldquoFrost front research of a cold-region tunnel considering ventilation based on a physicalmodel testrdquo Tunnelling and Underground Space Technologyvol 77 pp 261ndash279 2018

[22] G Zhang Y Guo Y Zhou et al ldquoExperimental study on thethermal performance of tunnel lining GHE under ground-water flowrdquo Applied =ermal Engineering vol 106 pp 784ndash795 2016

[23] G Zhang S Liu X Zhao et al ldquo-e coupling effect ofventilation and groundwater flow on the thermal performance

Advances in Civil Engineering 13

of tunnel lining GHEsrdquoApplied=ermal Engineering vol 112pp 595ndash605 2017

[24] Q Hu R Shi Y Hu et al ldquoMethod to evaluate the safety oftunnels through steeply inclined strata in cold regions basedon the sidewall frost heave modelrdquo Journal of Performance ofConstructed Facilities vol 32 2018

[25] H Cai P Li and Z Wu ldquoModel test of liquid nitrogenfreezing-temperature field of improved plastic freezing piperdquoJournal of Cold Regions Engineering vol 34 no 1 2020

[26] S E A Gehlin and G Hellstrom ldquoInfluence on thermalresponse test by groundwater flow in vertical fractures in hardrockrdquo Renewable Energy vol 28 no 14 pp 2221ndash2238 2003

14 Advances in Civil Engineering

Deicing of refrigerator Deicing of refrigerator

0 5 10 15 20 25 30Time (h)

0

2

4

6

8

10

12

14Te

mpe

ratu

re (deg

C)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(a)

Deicing of refrigeratorDeicing of refrigerator

0

2

4

6

8

10

12

14

Tem

pera

ture

(degC)

5 10 15 20 25 300Time (h)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(b)

Deicing of refrigerator

Groundwater seepage

TA TS9

1cm4cm 5cm

TS10 TS1118cm

Deicing of refrigerator

0

2

4

6

8

10

12

Tem

pera

ture

(degC)

5 10 15 20 25 300Time (h)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(c)

Figure 6 Variations in the surrounding rock temperature over time

8 Advances in Civil Engineering

seepage velocity increases -us the higher the groundwaterseepage velocity is the higher the temperature difference isbetween TS3 and TS6-e temperature difference between TS3and TS5 increases as the groundwater seepage velocity increasesfrom 0 to 0923md and decreases as the groundwater seepagevelocity increases from 0923 to 2743md Groundwaterseepage has a great effect on the interface temperature -iseffect has a spatial difference -us both the shape and size ofthe cross section of the tunnel significantly affect the interfacetemperature under groundwater seepage

34 Effect of Groundwater Seepage on the Freezing Damage toCold Region Tunnels -e tunnel drainage system is lo-cated between the lining and the surrounding rock

Monitoring points TS3 TS5 and TS6 are located at thetop middle and foot of the tunnel drainage systemrespectively -e temperatures at TS3 TS5 and TS6determine the antifreezing ability of cold region tunnels-erefore the higher the temperatures at TS3 TS5 andTS6 are the stronger the antifreezing capability of thetunnel in cold regions is Figure 8 shows that when thegroundwater seepage velocity is 0 md the measuringpoints TS3 TS5 and TS6 freeze synchronously If thetunnel surrounding rock is free of frost heaving coldregion tunnels may not need a thermal insulation layerWhen the groundwater seepage velocity is 0923 md themonitoring point TS6 freezes first -e interface thengradually freezes from TS6 to TS5 along the circumfer-ential direction of the tunnel section -is explains why

Tem

pera

ture

dro

p (deg

C)

Groundwater seepage

TS9TS10TS11

0

2

4

6

8

10

12

05 10 15 20 25 3000

18cm TA TS9 TS104cm

1cm5cm

TS11

Groundwater seepage velocity (md)

(a)

Tem

pera

ture

dro

p (deg

C)

TS9TS10TS11

Groundwater seepage

18cm TA TS9 TS104cm

1cm5cm

TS11

0

2

4

6

8

10

12

05 10 15 20 25 3000Groundwater seepage velocity (md)

(b)

Tem

pera

ture

dro

p (deg

C)

TS9TS10TS11

Groundwater seepage

18cm TA TS9 TS104cm

1cm5cm

TS11

0

2

4

6

8

10

12

05 10 15 20 25 3000Groundwater seepage velocity (md)

(c)

Figure 7 Variations in the surrounding rock temperature drop at different groundwater seepage velocities after 115 h of cooling Averagewind speed of (a) 0606ms (b) 1002ms and (c) 2398ms

Advances in Civil Engineering 9

ndash202468

101214

ndash202468

1012

Deicing of refrigeratorDeicing of refrigerator0degC

Deicing of refrigeratorDeicing of refrigerator

Deicing of refrigerator

0degC

Tem

pera

ture

(degC)

Tem

pera

ture

(degC)

ndash202468

101214

ndash202468

1012

Tem

pera

ture

(degC)

Tem

pera

ture

(degC)

Deicing of refrigerator Deicing of refrigerator

0degC 0degC

Deicing of refrigerator

0 5 10 15 20 25 30 0 5 10 15 20 25 30Time (h) Time (h)

0 5 10 15 20 25 30 0 5 10 15 20 25 30Time (h) Time (h)

(e)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(c) (d)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(a) (b)

ndash202468

1012

Tem

pera

ture

(degC)

ndash202468

1012

Tem

pera

ture

(degC)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Groundwater seepage

Deicing of refrigerator Deicing of refrigerator

0degC

0 5 10 15 20 25 30 0 5 10 15 20 25 30Time (h) Time (h)

TS1

TS6

TS5

TS4

TS3

18cmTA45deg

45deg

Figure 8 Variations in the temperature at the interface between the lining and the surrounding rock (a) TS1 (b) TS3 (c) TS4 (d) TS5 and(e) TS6

10 Advances in Civil Engineering

cold region tunnels suffer tunnel lining leakage and roadicing -e results of the model test reveal the cause oftunnel lining leakage and road icing To avoid tunnelleakage in cold region tunnels a thermal insulation layershould be properly designed and a heating device shouldbe installed in its longitudinal drainage pipe when thegroundwater seepage velocity is low When thegroundwater seepage velocity is 2743md the moni-toring point at TS6 freezes but the monitoring points atTS3 and TS5 do not Furthermore their temperatures do

not decrease significantly as cooling time increases-erefore the tunnel has good antifreezing capabilitywhen the groundwater seepage velocity is high -is goodantifreezing capability should be fully utilized Further-more the foot of the tunnel drainage system should bestrengthened against freezing via an insulation layer andheating device

-e above analysis demonstrates that cold region tunnelshave an antifreezing capability that is mainly related to the frostheaving of the surrounding rock and the groundwater seepage

Groundwater seepage

TS1TS3TS4

TS5TS6

Tem

pera

ture

dro

p (deg

C)

TA

TS3TS4

TS5

TS6TS1

45deg45deg

18cm

2

4

6

8

10

12

14

05 10 15 20 25 3000Groundwater seepage velocity (md)

(a)

TS1TS3TS4

TS5TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3TS4

TS5

TS6TS1

45deg45deg

18cm

2

4

6

8

10

12

14

05 10 15 20 25 3000Groundwater seepage velocity (md)

(b)

TS1TS3TS4

TS5TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3TS4

TS5

TS6TS1

45deg45deg

18cm

2

4

6

8

10

12

14

05 10 15 20 25 3000Groundwater seepage velocity (md)

(c)

Figure 9 Variations in the surrounding rock temperature drop at different groundwater seepage velocities after 115 h of cooling Averagewind speed of (a) 0606ms (b) 1002ms and (c) 2398ms

Advances in Civil Engineering 11

velocity -is antifreezing capability should be fully utilized inthe antifreezing design of cold region tunnels

4 Conclusions

A systematic study on the temperature field of cold regiontunnels is presented in which a model test that considers thecoupling effects of groundwater seepage and tunnel venti-lation is conducted -e effects of groundwater seepage onthe air temperature in the tunnel the surrounding rocktemperature the temperature at the interface between thelining and surrounding rock and the freezing damage of thetunnel in cold regions are studied -e following four mainconclusions are drawn

First groundwater seepage has a significant effect on theair temperature in the tunnel -e higher the groundwater

seepage velocity the higher the air temperature in thetunnel Groundwater seepage has a significant influence onthe thickness and length of the tunnel insulation layer in coldregions -e thickness and length of the tunnel insulationlayer can decrease under groundwater seepage

Second groundwater seepage and tunnel ventilationhave a coupling effect on the surrounding rock temperatureHigher groundwater seepage velocity and lower wind speedlead to higher surrounding rock temperature -e influenceof groundwater seepage and tunnel ventilation on thesurrounding rock temperature field is related to the depth ofthe surrounding rock

-ird groundwater seepage leads to an uneven tem-perature distribution at the interface between the lining andsurrounding rock -e tunnel ventilation further enhancesthis uneven temperature distribution -e groundwater

TS3-TS5TS3-TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3

TS5

TS6

45deg 18cm

ndash1

0

1

2

3

4

5

6

7

8

9

05 10 15 20 25 3000Groundwater seepage velocity (md)

(a)

TS3-TS5TS3-TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3

TS5

TS6

45deg 18cm

ndash1

0

1

2

3

4

5

6

7

8

9

05 10 15 20 25 3000Groundwater seepage velocity (md)

(b)

TS3-TS5TS3-TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3

TS5

TS6

45deg 18cm

ndash1

0

1

2

3

4

5

6

7

8

9

05 10 15 20 25 3000Groundwater seepage velocity (md)

(c)

Figure 10 Relationships between the temperature differences at TS5 TS6 and TS3 and groundwater seepage velocity Average wind speedof (a) 0606ms (b) 1002ms and (c) 2398ms

12 Advances in Civil Engineering

seepage and tunnel ventilation have a coupling effect on theinterface temperature -is coupling effect is related to theinterface location -e influence of the groundwater seepagevelocity on the interface temperature has a spatial difference-e shape and size of the cross section of the tunnel have asignificant influence on the interface temperature undergroundwater seepage

Fourth cold region tunnels have an antifreezing capa-bility that is mainly related to the frost heaving of thesurrounding rock and the groundwater seepage velocity-eantifreezing capability of the tunnel should be fully utilizedin the antifreezing design of cold region tunnels

Data Availability

-e data used to support the findings of this study areavailable from the corresponding author upon request

Conflicts of Interest

-e authors declare that they have no conflicts of interest

Acknowledgments

-is study was supported by the Key Laboratory of Geo-technical and Underground Engineering of Ministry ofEducation Tongji University (No KLE-TJGE-B1605) theKey Laboratory of Rock Mechanics and Geohazards ofZhejiang Province (No ZJRM-2018-Y-01) and the SichuanScience and Technology Program (No 2018GZ0359)

References

[1] S Li M Zhang W Pei and Y Lai ldquoExperimental and nu-merical simulations on heat-water-mechanics interactionmechanism in a freezing soilrdquo Applied =ermal Engineeringvol 132 pp 209ndash220 2018

[2] S Li M Zhang Y Tian W Pei and H Zhong ldquoExperimentaland numerical investigations on frost damage mechanism of acanal in cold regionsrdquo Cold Regions Science and Technologyvol 116 pp 1ndash11 2015

[3] S Shen C Xia J Huang and Y Li ldquoInfluence of seasonal meltlayer depth on the stability of surrounding rock in permafrostregions based on the measurementrdquoNatural Hazards vol 75no 3 pp 2545ndash2557 2015

[4] K-J Jun Y-C Hwang and C-Y Yune ldquoField measurementof temperature inside tunnel in winter in Gangwon KoreardquoCold Regions Science and Technology vol 143 pp 32ndash42 2017

[5] Q Ma X Luo Y Lai F Niu and J Gao ldquoNumerical in-vestigation on thermal insulation layer of a tunnel in sea-sonally frozen regionsrdquoApplied=ermal Engineering vol 138pp 280ndash291 2018

[6] X Zhao X Yang H Zhang H Lai and X Wang ldquoAnanalytical solution for frost heave force by the multifactor ofcoupled heat and moisture transfer in cold-region tunnelsrdquoCold Regions Science and Technology vol 175 2020

[7] Y M Lai S Y Liu Z W Wu and W Yu ldquoApproximateanalytical solution for temperature fields in cold regionscircular tunnelsrdquoCold Regions Science and Technology vol 34no 1 pp 43ndash49 2002

[8] G Zhang C Xia M Sun Y Zou and S Xiao ldquoA new modeland analytical solution for the heat conduction of tunnel

lining ground heat exchangersrdquo Cold Regions Science andTechnology vol 88 pp 59ndash66 2013

[9] Y M Lai Z W Wu Y L Zhu and L N Zhu ldquoNonlinearanalysis for the coupled problem of temperature seepage andstress fields in cold-region tunnelsrdquo Tunnelling and Under-ground Space Technology vol 13 no 4 pp 435ndash440 1998

[10] X Zhang J Xiao Y Zhang et al ldquoStudy of the function of theinsulation layer for treating water leakage in permafrosttunnelsrdquo Applied =ermal Engineering vol 27 no 2-3pp 637ndash645 2007

[11] X Zhang Y Lai W Yu and S Zhang ldquoNon-linear analysisfor the freezing-thawing situation of the rock surrounding thetunnel in cold regions under the conditions of differentconstruction seasons initial temperatures and insulationsrdquoTunnelling and Underground Space Technology vol 17 no 3pp 315ndash325 2002

[12] X Zhang Y Lai W Yu and Y Wu ldquoForecast analysis for there-frozen of Feng Huoshan permafrost tunnel on Qing-Zangrailwayrdquo Tunnelling and Underground Space Technologyvol 19 no 1 pp 45ndash56 2004

[13] X Tan W Chen H Tian and J Cao ldquoWater flow and heattransport including icewater phase change in porous medianumerical simulation and applicationrdquo Cold Regions Scienceand Technology vol 68 no 1-2 pp 74ndash84 2011

[14] X Tan W Chen G Wu and J Yang ldquoNumerical simulationsof heat transfer with ice-water phase change occurring inporous media and application to a cold-region tunnelrdquoTunnelling and Underground Space Technology vol 38pp 170ndash179 2013

[15] X Tan W Chen D Yang et al ldquoStudy on the influence ofairflow on the temperature of the surrounding rock in a coldregion tunnel and its application to insulation layer designrdquoApplied =ermal Engineering vol 67 no 1-2 pp 320ndash3342014

[16] S Li F Niu Y Lai W Pei and W Yu ldquoOptimal design ofthermal insulation layer of a tunnel in permafrost regionsbased on coupled heat-water simulationrdquo Applied =ermalEngineering vol 110 pp 1264ndash1273 2017

[17] Q Yan B Li Y Zhang J Yan and C Zhang ldquoNumericalinvestigation of heat-insulating layers in a cold region tunneltaking into account airflow and heat transferrdquo Applied Sci-ences vol 7 no 7 p 679 2017

[18] Q Feng B-S Jiang Q Zhang and G Wang ldquoReliabilityresearch on the 5-cm-thick insulation layer used in theYuximolegai tunnel based on a physical model testrdquo ColdRegions Science and Technology vol 124 pp 54ndash66 2016

[19] X Zhang Z Zhou J Li Y Zhou and F Han ldquoA physicalmodel experiment for investigating into temperature redis-tribution in surrounding rock of permafrost tunnelrdquo ColdRegions Science and Technology vol 151 pp 47ndash52 2018

[20] Y Zeng K Liu X Zhou and L Fan ldquoTunnel temperaturefields analysis under the couple effect of convection-con-duction in cold regionsrdquo Applied =ermal Engineeringvol 120 pp 378ndash392 2017

[21] L Liu Z Li X Liu and Y Li ldquoFrost front research of a cold-region tunnel considering ventilation based on a physicalmodel testrdquo Tunnelling and Underground Space Technologyvol 77 pp 261ndash279 2018

[22] G Zhang Y Guo Y Zhou et al ldquoExperimental study on thethermal performance of tunnel lining GHE under ground-water flowrdquo Applied =ermal Engineering vol 106 pp 784ndash795 2016

[23] G Zhang S Liu X Zhao et al ldquo-e coupling effect ofventilation and groundwater flow on the thermal performance

Advances in Civil Engineering 13

of tunnel lining GHEsrdquoApplied=ermal Engineering vol 112pp 595ndash605 2017

[24] Q Hu R Shi Y Hu et al ldquoMethod to evaluate the safety oftunnels through steeply inclined strata in cold regions basedon the sidewall frost heave modelrdquo Journal of Performance ofConstructed Facilities vol 32 2018

[25] H Cai P Li and Z Wu ldquoModel test of liquid nitrogenfreezing-temperature field of improved plastic freezing piperdquoJournal of Cold Regions Engineering vol 34 no 1 2020

[26] S E A Gehlin and G Hellstrom ldquoInfluence on thermalresponse test by groundwater flow in vertical fractures in hardrockrdquo Renewable Energy vol 28 no 14 pp 2221ndash2238 2003

14 Advances in Civil Engineering

seepage velocity increases -us the higher the groundwaterseepage velocity is the higher the temperature difference isbetween TS3 and TS6-e temperature difference between TS3and TS5 increases as the groundwater seepage velocity increasesfrom 0 to 0923md and decreases as the groundwater seepagevelocity increases from 0923 to 2743md Groundwaterseepage has a great effect on the interface temperature -iseffect has a spatial difference -us both the shape and size ofthe cross section of the tunnel significantly affect the interfacetemperature under groundwater seepage

34 Effect of Groundwater Seepage on the Freezing Damage toCold Region Tunnels -e tunnel drainage system is lo-cated between the lining and the surrounding rock

Monitoring points TS3 TS5 and TS6 are located at thetop middle and foot of the tunnel drainage systemrespectively -e temperatures at TS3 TS5 and TS6determine the antifreezing ability of cold region tunnels-erefore the higher the temperatures at TS3 TS5 andTS6 are the stronger the antifreezing capability of thetunnel in cold regions is Figure 8 shows that when thegroundwater seepage velocity is 0 md the measuringpoints TS3 TS5 and TS6 freeze synchronously If thetunnel surrounding rock is free of frost heaving coldregion tunnels may not need a thermal insulation layerWhen the groundwater seepage velocity is 0923 md themonitoring point TS6 freezes first -e interface thengradually freezes from TS6 to TS5 along the circumfer-ential direction of the tunnel section -is explains why

Tem

pera

ture

dro

p (deg

C)

Groundwater seepage

TS9TS10TS11

0

2

4

6

8

10

12

05 10 15 20 25 3000

18cm TA TS9 TS104cm

1cm5cm

TS11

Groundwater seepage velocity (md)

(a)

Tem

pera

ture

dro

p (deg

C)

TS9TS10TS11

Groundwater seepage

18cm TA TS9 TS104cm

1cm5cm

TS11

0

2

4

6

8

10

12

05 10 15 20 25 3000Groundwater seepage velocity (md)

(b)

Tem

pera

ture

dro

p (deg

C)

TS9TS10TS11

Groundwater seepage

18cm TA TS9 TS104cm

1cm5cm

TS11

0

2

4

6

8

10

12

05 10 15 20 25 3000Groundwater seepage velocity (md)

(c)

Figure 7 Variations in the surrounding rock temperature drop at different groundwater seepage velocities after 115 h of cooling Averagewind speed of (a) 0606ms (b) 1002ms and (c) 2398ms

Advances in Civil Engineering 9

ndash202468

101214

ndash202468

1012

Deicing of refrigeratorDeicing of refrigerator0degC

Deicing of refrigeratorDeicing of refrigerator

Deicing of refrigerator

0degC

Tem

pera

ture

(degC)

Tem

pera

ture

(degC)

ndash202468

101214

ndash202468

1012

Tem

pera

ture

(degC)

Tem

pera

ture

(degC)

Deicing of refrigerator Deicing of refrigerator

0degC 0degC

Deicing of refrigerator

0 5 10 15 20 25 30 0 5 10 15 20 25 30Time (h) Time (h)

0 5 10 15 20 25 30 0 5 10 15 20 25 30Time (h) Time (h)

(e)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(c) (d)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(a) (b)

ndash202468

1012

Tem

pera

ture

(degC)

ndash202468

1012

Tem

pera

ture

(degC)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Groundwater seepage

Deicing of refrigerator Deicing of refrigerator

0degC

0 5 10 15 20 25 30 0 5 10 15 20 25 30Time (h) Time (h)

TS1

TS6

TS5

TS4

TS3

18cmTA45deg

45deg

Figure 8 Variations in the temperature at the interface between the lining and the surrounding rock (a) TS1 (b) TS3 (c) TS4 (d) TS5 and(e) TS6

10 Advances in Civil Engineering

cold region tunnels suffer tunnel lining leakage and roadicing -e results of the model test reveal the cause oftunnel lining leakage and road icing To avoid tunnelleakage in cold region tunnels a thermal insulation layershould be properly designed and a heating device shouldbe installed in its longitudinal drainage pipe when thegroundwater seepage velocity is low When thegroundwater seepage velocity is 2743md the moni-toring point at TS6 freezes but the monitoring points atTS3 and TS5 do not Furthermore their temperatures do

not decrease significantly as cooling time increases-erefore the tunnel has good antifreezing capabilitywhen the groundwater seepage velocity is high -is goodantifreezing capability should be fully utilized Further-more the foot of the tunnel drainage system should bestrengthened against freezing via an insulation layer andheating device

-e above analysis demonstrates that cold region tunnelshave an antifreezing capability that is mainly related to the frostheaving of the surrounding rock and the groundwater seepage

Groundwater seepage

TS1TS3TS4

TS5TS6

Tem

pera

ture

dro

p (deg

C)

TA

TS3TS4

TS5

TS6TS1

45deg45deg

18cm

2

4

6

8

10

12

14

05 10 15 20 25 3000Groundwater seepage velocity (md)

(a)

TS1TS3TS4

TS5TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3TS4

TS5

TS6TS1

45deg45deg

18cm

2

4

6

8

10

12

14

05 10 15 20 25 3000Groundwater seepage velocity (md)

(b)

TS1TS3TS4

TS5TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3TS4

TS5

TS6TS1

45deg45deg

18cm

2

4

6

8

10

12

14

05 10 15 20 25 3000Groundwater seepage velocity (md)

(c)

Figure 9 Variations in the surrounding rock temperature drop at different groundwater seepage velocities after 115 h of cooling Averagewind speed of (a) 0606ms (b) 1002ms and (c) 2398ms

Advances in Civil Engineering 11

velocity -is antifreezing capability should be fully utilized inthe antifreezing design of cold region tunnels

4 Conclusions

A systematic study on the temperature field of cold regiontunnels is presented in which a model test that considers thecoupling effects of groundwater seepage and tunnel venti-lation is conducted -e effects of groundwater seepage onthe air temperature in the tunnel the surrounding rocktemperature the temperature at the interface between thelining and surrounding rock and the freezing damage of thetunnel in cold regions are studied -e following four mainconclusions are drawn

First groundwater seepage has a significant effect on theair temperature in the tunnel -e higher the groundwater

seepage velocity the higher the air temperature in thetunnel Groundwater seepage has a significant influence onthe thickness and length of the tunnel insulation layer in coldregions -e thickness and length of the tunnel insulationlayer can decrease under groundwater seepage

Second groundwater seepage and tunnel ventilationhave a coupling effect on the surrounding rock temperatureHigher groundwater seepage velocity and lower wind speedlead to higher surrounding rock temperature -e influenceof groundwater seepage and tunnel ventilation on thesurrounding rock temperature field is related to the depth ofthe surrounding rock

-ird groundwater seepage leads to an uneven tem-perature distribution at the interface between the lining andsurrounding rock -e tunnel ventilation further enhancesthis uneven temperature distribution -e groundwater

TS3-TS5TS3-TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3

TS5

TS6

45deg 18cm

ndash1

0

1

2

3

4

5

6

7

8

9

05 10 15 20 25 3000Groundwater seepage velocity (md)

(a)

TS3-TS5TS3-TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3

TS5

TS6

45deg 18cm

ndash1

0

1

2

3

4

5

6

7

8

9

05 10 15 20 25 3000Groundwater seepage velocity (md)

(b)

TS3-TS5TS3-TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3

TS5

TS6

45deg 18cm

ndash1

0

1

2

3

4

5

6

7

8

9

05 10 15 20 25 3000Groundwater seepage velocity (md)

(c)

Figure 10 Relationships between the temperature differences at TS5 TS6 and TS3 and groundwater seepage velocity Average wind speedof (a) 0606ms (b) 1002ms and (c) 2398ms

12 Advances in Civil Engineering

seepage and tunnel ventilation have a coupling effect on theinterface temperature -is coupling effect is related to theinterface location -e influence of the groundwater seepagevelocity on the interface temperature has a spatial difference-e shape and size of the cross section of the tunnel have asignificant influence on the interface temperature undergroundwater seepage

Fourth cold region tunnels have an antifreezing capa-bility that is mainly related to the frost heaving of thesurrounding rock and the groundwater seepage velocity-eantifreezing capability of the tunnel should be fully utilizedin the antifreezing design of cold region tunnels

Data Availability

-e data used to support the findings of this study areavailable from the corresponding author upon request

Conflicts of Interest

-e authors declare that they have no conflicts of interest

Acknowledgments

-is study was supported by the Key Laboratory of Geo-technical and Underground Engineering of Ministry ofEducation Tongji University (No KLE-TJGE-B1605) theKey Laboratory of Rock Mechanics and Geohazards ofZhejiang Province (No ZJRM-2018-Y-01) and the SichuanScience and Technology Program (No 2018GZ0359)

References

[1] S Li M Zhang W Pei and Y Lai ldquoExperimental and nu-merical simulations on heat-water-mechanics interactionmechanism in a freezing soilrdquo Applied =ermal Engineeringvol 132 pp 209ndash220 2018

[2] S Li M Zhang Y Tian W Pei and H Zhong ldquoExperimentaland numerical investigations on frost damage mechanism of acanal in cold regionsrdquo Cold Regions Science and Technologyvol 116 pp 1ndash11 2015

[3] S Shen C Xia J Huang and Y Li ldquoInfluence of seasonal meltlayer depth on the stability of surrounding rock in permafrostregions based on the measurementrdquoNatural Hazards vol 75no 3 pp 2545ndash2557 2015

[4] K-J Jun Y-C Hwang and C-Y Yune ldquoField measurementof temperature inside tunnel in winter in Gangwon KoreardquoCold Regions Science and Technology vol 143 pp 32ndash42 2017

[5] Q Ma X Luo Y Lai F Niu and J Gao ldquoNumerical in-vestigation on thermal insulation layer of a tunnel in sea-sonally frozen regionsrdquoApplied=ermal Engineering vol 138pp 280ndash291 2018

[6] X Zhao X Yang H Zhang H Lai and X Wang ldquoAnanalytical solution for frost heave force by the multifactor ofcoupled heat and moisture transfer in cold-region tunnelsrdquoCold Regions Science and Technology vol 175 2020

[7] Y M Lai S Y Liu Z W Wu and W Yu ldquoApproximateanalytical solution for temperature fields in cold regionscircular tunnelsrdquoCold Regions Science and Technology vol 34no 1 pp 43ndash49 2002

[8] G Zhang C Xia M Sun Y Zou and S Xiao ldquoA new modeland analytical solution for the heat conduction of tunnel

lining ground heat exchangersrdquo Cold Regions Science andTechnology vol 88 pp 59ndash66 2013

[9] Y M Lai Z W Wu Y L Zhu and L N Zhu ldquoNonlinearanalysis for the coupled problem of temperature seepage andstress fields in cold-region tunnelsrdquo Tunnelling and Under-ground Space Technology vol 13 no 4 pp 435ndash440 1998

[10] X Zhang J Xiao Y Zhang et al ldquoStudy of the function of theinsulation layer for treating water leakage in permafrosttunnelsrdquo Applied =ermal Engineering vol 27 no 2-3pp 637ndash645 2007

[11] X Zhang Y Lai W Yu and S Zhang ldquoNon-linear analysisfor the freezing-thawing situation of the rock surrounding thetunnel in cold regions under the conditions of differentconstruction seasons initial temperatures and insulationsrdquoTunnelling and Underground Space Technology vol 17 no 3pp 315ndash325 2002

[12] X Zhang Y Lai W Yu and Y Wu ldquoForecast analysis for there-frozen of Feng Huoshan permafrost tunnel on Qing-Zangrailwayrdquo Tunnelling and Underground Space Technologyvol 19 no 1 pp 45ndash56 2004

[13] X Tan W Chen H Tian and J Cao ldquoWater flow and heattransport including icewater phase change in porous medianumerical simulation and applicationrdquo Cold Regions Scienceand Technology vol 68 no 1-2 pp 74ndash84 2011

[14] X Tan W Chen G Wu and J Yang ldquoNumerical simulationsof heat transfer with ice-water phase change occurring inporous media and application to a cold-region tunnelrdquoTunnelling and Underground Space Technology vol 38pp 170ndash179 2013

[15] X Tan W Chen D Yang et al ldquoStudy on the influence ofairflow on the temperature of the surrounding rock in a coldregion tunnel and its application to insulation layer designrdquoApplied =ermal Engineering vol 67 no 1-2 pp 320ndash3342014

[16] S Li F Niu Y Lai W Pei and W Yu ldquoOptimal design ofthermal insulation layer of a tunnel in permafrost regionsbased on coupled heat-water simulationrdquo Applied =ermalEngineering vol 110 pp 1264ndash1273 2017

[17] Q Yan B Li Y Zhang J Yan and C Zhang ldquoNumericalinvestigation of heat-insulating layers in a cold region tunneltaking into account airflow and heat transferrdquo Applied Sci-ences vol 7 no 7 p 679 2017

[18] Q Feng B-S Jiang Q Zhang and G Wang ldquoReliabilityresearch on the 5-cm-thick insulation layer used in theYuximolegai tunnel based on a physical model testrdquo ColdRegions Science and Technology vol 124 pp 54ndash66 2016

[19] X Zhang Z Zhou J Li Y Zhou and F Han ldquoA physicalmodel experiment for investigating into temperature redis-tribution in surrounding rock of permafrost tunnelrdquo ColdRegions Science and Technology vol 151 pp 47ndash52 2018

[20] Y Zeng K Liu X Zhou and L Fan ldquoTunnel temperaturefields analysis under the couple effect of convection-con-duction in cold regionsrdquo Applied =ermal Engineeringvol 120 pp 378ndash392 2017

[21] L Liu Z Li X Liu and Y Li ldquoFrost front research of a cold-region tunnel considering ventilation based on a physicalmodel testrdquo Tunnelling and Underground Space Technologyvol 77 pp 261ndash279 2018

[22] G Zhang Y Guo Y Zhou et al ldquoExperimental study on thethermal performance of tunnel lining GHE under ground-water flowrdquo Applied =ermal Engineering vol 106 pp 784ndash795 2016

[23] G Zhang S Liu X Zhao et al ldquo-e coupling effect ofventilation and groundwater flow on the thermal performance

Advances in Civil Engineering 13

of tunnel lining GHEsrdquoApplied=ermal Engineering vol 112pp 595ndash605 2017

[24] Q Hu R Shi Y Hu et al ldquoMethod to evaluate the safety oftunnels through steeply inclined strata in cold regions basedon the sidewall frost heave modelrdquo Journal of Performance ofConstructed Facilities vol 32 2018

[25] H Cai P Li and Z Wu ldquoModel test of liquid nitrogenfreezing-temperature field of improved plastic freezing piperdquoJournal of Cold Regions Engineering vol 34 no 1 2020

[26] S E A Gehlin and G Hellstrom ldquoInfluence on thermalresponse test by groundwater flow in vertical fractures in hardrockrdquo Renewable Energy vol 28 no 14 pp 2221ndash2238 2003

14 Advances in Civil Engineering

ndash202468

101214

ndash202468

1012

Deicing of refrigeratorDeicing of refrigerator0degC

Deicing of refrigeratorDeicing of refrigerator

Deicing of refrigerator

0degC

Tem

pera

ture

(degC)

Tem

pera

ture

(degC)

ndash202468

101214

ndash202468

1012

Tem

pera

ture

(degC)

Tem

pera

ture

(degC)

Deicing of refrigerator Deicing of refrigerator

0degC 0degC

Deicing of refrigerator

0 5 10 15 20 25 30 0 5 10 15 20 25 30Time (h) Time (h)

0 5 10 15 20 25 30 0 5 10 15 20 25 30Time (h) Time (h)

(e)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(c) (d)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

(a) (b)

ndash202468

1012

Tem

pera

ture

(degC)

ndash202468

1012

Tem

pera

ture

(degC)

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Vw = 0606ms VL = 0mdVw = 1002ms VL = 0mdVw = 2398ms VL = 0mdVw = 0606ms VL = 0923mdVw = 1002ms VL = 0923mdVw = 2398ms VL = 0923mdVw = 0606ms VL = 2743mdVw = 1002ms VL = 2743mdVw = 2398ms VL = 2743md

Groundwater seepage

Deicing of refrigerator Deicing of refrigerator

0degC

0 5 10 15 20 25 30 0 5 10 15 20 25 30Time (h) Time (h)

TS1

TS6

TS5

TS4

TS3

18cmTA45deg

45deg

Figure 8 Variations in the temperature at the interface between the lining and the surrounding rock (a) TS1 (b) TS3 (c) TS4 (d) TS5 and(e) TS6

10 Advances in Civil Engineering

cold region tunnels suffer tunnel lining leakage and roadicing -e results of the model test reveal the cause oftunnel lining leakage and road icing To avoid tunnelleakage in cold region tunnels a thermal insulation layershould be properly designed and a heating device shouldbe installed in its longitudinal drainage pipe when thegroundwater seepage velocity is low When thegroundwater seepage velocity is 2743md the moni-toring point at TS6 freezes but the monitoring points atTS3 and TS5 do not Furthermore their temperatures do

not decrease significantly as cooling time increases-erefore the tunnel has good antifreezing capabilitywhen the groundwater seepage velocity is high -is goodantifreezing capability should be fully utilized Further-more the foot of the tunnel drainage system should bestrengthened against freezing via an insulation layer andheating device

-e above analysis demonstrates that cold region tunnelshave an antifreezing capability that is mainly related to the frostheaving of the surrounding rock and the groundwater seepage

Groundwater seepage

TS1TS3TS4

TS5TS6

Tem

pera

ture

dro

p (deg

C)

TA

TS3TS4

TS5

TS6TS1

45deg45deg

18cm

2

4

6

8

10

12

14

05 10 15 20 25 3000Groundwater seepage velocity (md)

(a)

TS1TS3TS4

TS5TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3TS4

TS5

TS6TS1

45deg45deg

18cm

2

4

6

8

10

12

14

05 10 15 20 25 3000Groundwater seepage velocity (md)

(b)

TS1TS3TS4

TS5TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3TS4

TS5

TS6TS1

45deg45deg

18cm

2

4

6

8

10

12

14

05 10 15 20 25 3000Groundwater seepage velocity (md)

(c)

Figure 9 Variations in the surrounding rock temperature drop at different groundwater seepage velocities after 115 h of cooling Averagewind speed of (a) 0606ms (b) 1002ms and (c) 2398ms

Advances in Civil Engineering 11

velocity -is antifreezing capability should be fully utilized inthe antifreezing design of cold region tunnels

4 Conclusions

A systematic study on the temperature field of cold regiontunnels is presented in which a model test that considers thecoupling effects of groundwater seepage and tunnel venti-lation is conducted -e effects of groundwater seepage onthe air temperature in the tunnel the surrounding rocktemperature the temperature at the interface between thelining and surrounding rock and the freezing damage of thetunnel in cold regions are studied -e following four mainconclusions are drawn

First groundwater seepage has a significant effect on theair temperature in the tunnel -e higher the groundwater

seepage velocity the higher the air temperature in thetunnel Groundwater seepage has a significant influence onthe thickness and length of the tunnel insulation layer in coldregions -e thickness and length of the tunnel insulationlayer can decrease under groundwater seepage

Second groundwater seepage and tunnel ventilationhave a coupling effect on the surrounding rock temperatureHigher groundwater seepage velocity and lower wind speedlead to higher surrounding rock temperature -e influenceof groundwater seepage and tunnel ventilation on thesurrounding rock temperature field is related to the depth ofthe surrounding rock

-ird groundwater seepage leads to an uneven tem-perature distribution at the interface between the lining andsurrounding rock -e tunnel ventilation further enhancesthis uneven temperature distribution -e groundwater

TS3-TS5TS3-TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3

TS5

TS6

45deg 18cm

ndash1

0

1

2

3

4

5

6

7

8

9

05 10 15 20 25 3000Groundwater seepage velocity (md)

(a)

TS3-TS5TS3-TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3

TS5

TS6

45deg 18cm

ndash1

0

1

2

3

4

5

6

7

8

9

05 10 15 20 25 3000Groundwater seepage velocity (md)

(b)

TS3-TS5TS3-TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3

TS5

TS6

45deg 18cm

ndash1

0

1

2

3

4

5

6

7

8

9

05 10 15 20 25 3000Groundwater seepage velocity (md)

(c)

Figure 10 Relationships between the temperature differences at TS5 TS6 and TS3 and groundwater seepage velocity Average wind speedof (a) 0606ms (b) 1002ms and (c) 2398ms

12 Advances in Civil Engineering

seepage and tunnel ventilation have a coupling effect on theinterface temperature -is coupling effect is related to theinterface location -e influence of the groundwater seepagevelocity on the interface temperature has a spatial difference-e shape and size of the cross section of the tunnel have asignificant influence on the interface temperature undergroundwater seepage

Fourth cold region tunnels have an antifreezing capa-bility that is mainly related to the frost heaving of thesurrounding rock and the groundwater seepage velocity-eantifreezing capability of the tunnel should be fully utilizedin the antifreezing design of cold region tunnels

Data Availability

-e data used to support the findings of this study areavailable from the corresponding author upon request

Conflicts of Interest

-e authors declare that they have no conflicts of interest

Acknowledgments

-is study was supported by the Key Laboratory of Geo-technical and Underground Engineering of Ministry ofEducation Tongji University (No KLE-TJGE-B1605) theKey Laboratory of Rock Mechanics and Geohazards ofZhejiang Province (No ZJRM-2018-Y-01) and the SichuanScience and Technology Program (No 2018GZ0359)

References

[1] S Li M Zhang W Pei and Y Lai ldquoExperimental and nu-merical simulations on heat-water-mechanics interactionmechanism in a freezing soilrdquo Applied =ermal Engineeringvol 132 pp 209ndash220 2018

[2] S Li M Zhang Y Tian W Pei and H Zhong ldquoExperimentaland numerical investigations on frost damage mechanism of acanal in cold regionsrdquo Cold Regions Science and Technologyvol 116 pp 1ndash11 2015

[3] S Shen C Xia J Huang and Y Li ldquoInfluence of seasonal meltlayer depth on the stability of surrounding rock in permafrostregions based on the measurementrdquoNatural Hazards vol 75no 3 pp 2545ndash2557 2015

[4] K-J Jun Y-C Hwang and C-Y Yune ldquoField measurementof temperature inside tunnel in winter in Gangwon KoreardquoCold Regions Science and Technology vol 143 pp 32ndash42 2017

[5] Q Ma X Luo Y Lai F Niu and J Gao ldquoNumerical in-vestigation on thermal insulation layer of a tunnel in sea-sonally frozen regionsrdquoApplied=ermal Engineering vol 138pp 280ndash291 2018

[6] X Zhao X Yang H Zhang H Lai and X Wang ldquoAnanalytical solution for frost heave force by the multifactor ofcoupled heat and moisture transfer in cold-region tunnelsrdquoCold Regions Science and Technology vol 175 2020

[7] Y M Lai S Y Liu Z W Wu and W Yu ldquoApproximateanalytical solution for temperature fields in cold regionscircular tunnelsrdquoCold Regions Science and Technology vol 34no 1 pp 43ndash49 2002

[8] G Zhang C Xia M Sun Y Zou and S Xiao ldquoA new modeland analytical solution for the heat conduction of tunnel

lining ground heat exchangersrdquo Cold Regions Science andTechnology vol 88 pp 59ndash66 2013

[9] Y M Lai Z W Wu Y L Zhu and L N Zhu ldquoNonlinearanalysis for the coupled problem of temperature seepage andstress fields in cold-region tunnelsrdquo Tunnelling and Under-ground Space Technology vol 13 no 4 pp 435ndash440 1998

[10] X Zhang J Xiao Y Zhang et al ldquoStudy of the function of theinsulation layer for treating water leakage in permafrosttunnelsrdquo Applied =ermal Engineering vol 27 no 2-3pp 637ndash645 2007

[11] X Zhang Y Lai W Yu and S Zhang ldquoNon-linear analysisfor the freezing-thawing situation of the rock surrounding thetunnel in cold regions under the conditions of differentconstruction seasons initial temperatures and insulationsrdquoTunnelling and Underground Space Technology vol 17 no 3pp 315ndash325 2002

[12] X Zhang Y Lai W Yu and Y Wu ldquoForecast analysis for there-frozen of Feng Huoshan permafrost tunnel on Qing-Zangrailwayrdquo Tunnelling and Underground Space Technologyvol 19 no 1 pp 45ndash56 2004

[13] X Tan W Chen H Tian and J Cao ldquoWater flow and heattransport including icewater phase change in porous medianumerical simulation and applicationrdquo Cold Regions Scienceand Technology vol 68 no 1-2 pp 74ndash84 2011

[14] X Tan W Chen G Wu and J Yang ldquoNumerical simulationsof heat transfer with ice-water phase change occurring inporous media and application to a cold-region tunnelrdquoTunnelling and Underground Space Technology vol 38pp 170ndash179 2013

[15] X Tan W Chen D Yang et al ldquoStudy on the influence ofairflow on the temperature of the surrounding rock in a coldregion tunnel and its application to insulation layer designrdquoApplied =ermal Engineering vol 67 no 1-2 pp 320ndash3342014

[16] S Li F Niu Y Lai W Pei and W Yu ldquoOptimal design ofthermal insulation layer of a tunnel in permafrost regionsbased on coupled heat-water simulationrdquo Applied =ermalEngineering vol 110 pp 1264ndash1273 2017

[17] Q Yan B Li Y Zhang J Yan and C Zhang ldquoNumericalinvestigation of heat-insulating layers in a cold region tunneltaking into account airflow and heat transferrdquo Applied Sci-ences vol 7 no 7 p 679 2017

[18] Q Feng B-S Jiang Q Zhang and G Wang ldquoReliabilityresearch on the 5-cm-thick insulation layer used in theYuximolegai tunnel based on a physical model testrdquo ColdRegions Science and Technology vol 124 pp 54ndash66 2016

[19] X Zhang Z Zhou J Li Y Zhou and F Han ldquoA physicalmodel experiment for investigating into temperature redis-tribution in surrounding rock of permafrost tunnelrdquo ColdRegions Science and Technology vol 151 pp 47ndash52 2018

[20] Y Zeng K Liu X Zhou and L Fan ldquoTunnel temperaturefields analysis under the couple effect of convection-con-duction in cold regionsrdquo Applied =ermal Engineeringvol 120 pp 378ndash392 2017

[21] L Liu Z Li X Liu and Y Li ldquoFrost front research of a cold-region tunnel considering ventilation based on a physicalmodel testrdquo Tunnelling and Underground Space Technologyvol 77 pp 261ndash279 2018

[22] G Zhang Y Guo Y Zhou et al ldquoExperimental study on thethermal performance of tunnel lining GHE under ground-water flowrdquo Applied =ermal Engineering vol 106 pp 784ndash795 2016

[23] G Zhang S Liu X Zhao et al ldquo-e coupling effect ofventilation and groundwater flow on the thermal performance

Advances in Civil Engineering 13

of tunnel lining GHEsrdquoApplied=ermal Engineering vol 112pp 595ndash605 2017

[24] Q Hu R Shi Y Hu et al ldquoMethod to evaluate the safety oftunnels through steeply inclined strata in cold regions basedon the sidewall frost heave modelrdquo Journal of Performance ofConstructed Facilities vol 32 2018

[25] H Cai P Li and Z Wu ldquoModel test of liquid nitrogenfreezing-temperature field of improved plastic freezing piperdquoJournal of Cold Regions Engineering vol 34 no 1 2020

[26] S E A Gehlin and G Hellstrom ldquoInfluence on thermalresponse test by groundwater flow in vertical fractures in hardrockrdquo Renewable Energy vol 28 no 14 pp 2221ndash2238 2003

14 Advances in Civil Engineering

cold region tunnels suffer tunnel lining leakage and roadicing -e results of the model test reveal the cause oftunnel lining leakage and road icing To avoid tunnelleakage in cold region tunnels a thermal insulation layershould be properly designed and a heating device shouldbe installed in its longitudinal drainage pipe when thegroundwater seepage velocity is low When thegroundwater seepage velocity is 2743md the moni-toring point at TS6 freezes but the monitoring points atTS3 and TS5 do not Furthermore their temperatures do

not decrease significantly as cooling time increases-erefore the tunnel has good antifreezing capabilitywhen the groundwater seepage velocity is high -is goodantifreezing capability should be fully utilized Further-more the foot of the tunnel drainage system should bestrengthened against freezing via an insulation layer andheating device

-e above analysis demonstrates that cold region tunnelshave an antifreezing capability that is mainly related to the frostheaving of the surrounding rock and the groundwater seepage

Groundwater seepage

TS1TS3TS4

TS5TS6

Tem

pera

ture

dro

p (deg

C)

TA

TS3TS4

TS5

TS6TS1

45deg45deg

18cm

2

4

6

8

10

12

14

05 10 15 20 25 3000Groundwater seepage velocity (md)

(a)

TS1TS3TS4

TS5TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3TS4

TS5

TS6TS1

45deg45deg

18cm

2

4

6

8

10

12

14

05 10 15 20 25 3000Groundwater seepage velocity (md)

(b)

TS1TS3TS4

TS5TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3TS4

TS5

TS6TS1

45deg45deg

18cm

2

4

6

8

10

12

14

05 10 15 20 25 3000Groundwater seepage velocity (md)

(c)

Figure 9 Variations in the surrounding rock temperature drop at different groundwater seepage velocities after 115 h of cooling Averagewind speed of (a) 0606ms (b) 1002ms and (c) 2398ms

Advances in Civil Engineering 11

velocity -is antifreezing capability should be fully utilized inthe antifreezing design of cold region tunnels

4 Conclusions

A systematic study on the temperature field of cold regiontunnels is presented in which a model test that considers thecoupling effects of groundwater seepage and tunnel venti-lation is conducted -e effects of groundwater seepage onthe air temperature in the tunnel the surrounding rocktemperature the temperature at the interface between thelining and surrounding rock and the freezing damage of thetunnel in cold regions are studied -e following four mainconclusions are drawn

First groundwater seepage has a significant effect on theair temperature in the tunnel -e higher the groundwater

seepage velocity the higher the air temperature in thetunnel Groundwater seepage has a significant influence onthe thickness and length of the tunnel insulation layer in coldregions -e thickness and length of the tunnel insulationlayer can decrease under groundwater seepage

Second groundwater seepage and tunnel ventilationhave a coupling effect on the surrounding rock temperatureHigher groundwater seepage velocity and lower wind speedlead to higher surrounding rock temperature -e influenceof groundwater seepage and tunnel ventilation on thesurrounding rock temperature field is related to the depth ofthe surrounding rock

-ird groundwater seepage leads to an uneven tem-perature distribution at the interface between the lining andsurrounding rock -e tunnel ventilation further enhancesthis uneven temperature distribution -e groundwater

TS3-TS5TS3-TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3

TS5

TS6

45deg 18cm

ndash1

0

1

2

3

4

5

6

7

8

9

05 10 15 20 25 3000Groundwater seepage velocity (md)

(a)

TS3-TS5TS3-TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3

TS5

TS6

45deg 18cm

ndash1

0

1

2

3

4

5

6

7

8

9

05 10 15 20 25 3000Groundwater seepage velocity (md)

(b)

TS3-TS5TS3-TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3

TS5

TS6

45deg 18cm

ndash1

0

1

2

3

4

5

6

7

8

9

05 10 15 20 25 3000Groundwater seepage velocity (md)

(c)

Figure 10 Relationships between the temperature differences at TS5 TS6 and TS3 and groundwater seepage velocity Average wind speedof (a) 0606ms (b) 1002ms and (c) 2398ms

12 Advances in Civil Engineering

seepage and tunnel ventilation have a coupling effect on theinterface temperature -is coupling effect is related to theinterface location -e influence of the groundwater seepagevelocity on the interface temperature has a spatial difference-e shape and size of the cross section of the tunnel have asignificant influence on the interface temperature undergroundwater seepage

Fourth cold region tunnels have an antifreezing capa-bility that is mainly related to the frost heaving of thesurrounding rock and the groundwater seepage velocity-eantifreezing capability of the tunnel should be fully utilizedin the antifreezing design of cold region tunnels

Data Availability

-e data used to support the findings of this study areavailable from the corresponding author upon request

Conflicts of Interest

-e authors declare that they have no conflicts of interest

Acknowledgments

-is study was supported by the Key Laboratory of Geo-technical and Underground Engineering of Ministry ofEducation Tongji University (No KLE-TJGE-B1605) theKey Laboratory of Rock Mechanics and Geohazards ofZhejiang Province (No ZJRM-2018-Y-01) and the SichuanScience and Technology Program (No 2018GZ0359)

References

[1] S Li M Zhang W Pei and Y Lai ldquoExperimental and nu-merical simulations on heat-water-mechanics interactionmechanism in a freezing soilrdquo Applied =ermal Engineeringvol 132 pp 209ndash220 2018

[2] S Li M Zhang Y Tian W Pei and H Zhong ldquoExperimentaland numerical investigations on frost damage mechanism of acanal in cold regionsrdquo Cold Regions Science and Technologyvol 116 pp 1ndash11 2015

[3] S Shen C Xia J Huang and Y Li ldquoInfluence of seasonal meltlayer depth on the stability of surrounding rock in permafrostregions based on the measurementrdquoNatural Hazards vol 75no 3 pp 2545ndash2557 2015

[4] K-J Jun Y-C Hwang and C-Y Yune ldquoField measurementof temperature inside tunnel in winter in Gangwon KoreardquoCold Regions Science and Technology vol 143 pp 32ndash42 2017

[5] Q Ma X Luo Y Lai F Niu and J Gao ldquoNumerical in-vestigation on thermal insulation layer of a tunnel in sea-sonally frozen regionsrdquoApplied=ermal Engineering vol 138pp 280ndash291 2018

[6] X Zhao X Yang H Zhang H Lai and X Wang ldquoAnanalytical solution for frost heave force by the multifactor ofcoupled heat and moisture transfer in cold-region tunnelsrdquoCold Regions Science and Technology vol 175 2020

[7] Y M Lai S Y Liu Z W Wu and W Yu ldquoApproximateanalytical solution for temperature fields in cold regionscircular tunnelsrdquoCold Regions Science and Technology vol 34no 1 pp 43ndash49 2002

[8] G Zhang C Xia M Sun Y Zou and S Xiao ldquoA new modeland analytical solution for the heat conduction of tunnel

lining ground heat exchangersrdquo Cold Regions Science andTechnology vol 88 pp 59ndash66 2013

[9] Y M Lai Z W Wu Y L Zhu and L N Zhu ldquoNonlinearanalysis for the coupled problem of temperature seepage andstress fields in cold-region tunnelsrdquo Tunnelling and Under-ground Space Technology vol 13 no 4 pp 435ndash440 1998

[10] X Zhang J Xiao Y Zhang et al ldquoStudy of the function of theinsulation layer for treating water leakage in permafrosttunnelsrdquo Applied =ermal Engineering vol 27 no 2-3pp 637ndash645 2007

[11] X Zhang Y Lai W Yu and S Zhang ldquoNon-linear analysisfor the freezing-thawing situation of the rock surrounding thetunnel in cold regions under the conditions of differentconstruction seasons initial temperatures and insulationsrdquoTunnelling and Underground Space Technology vol 17 no 3pp 315ndash325 2002

[12] X Zhang Y Lai W Yu and Y Wu ldquoForecast analysis for there-frozen of Feng Huoshan permafrost tunnel on Qing-Zangrailwayrdquo Tunnelling and Underground Space Technologyvol 19 no 1 pp 45ndash56 2004

[13] X Tan W Chen H Tian and J Cao ldquoWater flow and heattransport including icewater phase change in porous medianumerical simulation and applicationrdquo Cold Regions Scienceand Technology vol 68 no 1-2 pp 74ndash84 2011

[14] X Tan W Chen G Wu and J Yang ldquoNumerical simulationsof heat transfer with ice-water phase change occurring inporous media and application to a cold-region tunnelrdquoTunnelling and Underground Space Technology vol 38pp 170ndash179 2013

[15] X Tan W Chen D Yang et al ldquoStudy on the influence ofairflow on the temperature of the surrounding rock in a coldregion tunnel and its application to insulation layer designrdquoApplied =ermal Engineering vol 67 no 1-2 pp 320ndash3342014

[16] S Li F Niu Y Lai W Pei and W Yu ldquoOptimal design ofthermal insulation layer of a tunnel in permafrost regionsbased on coupled heat-water simulationrdquo Applied =ermalEngineering vol 110 pp 1264ndash1273 2017

[17] Q Yan B Li Y Zhang J Yan and C Zhang ldquoNumericalinvestigation of heat-insulating layers in a cold region tunneltaking into account airflow and heat transferrdquo Applied Sci-ences vol 7 no 7 p 679 2017

[18] Q Feng B-S Jiang Q Zhang and G Wang ldquoReliabilityresearch on the 5-cm-thick insulation layer used in theYuximolegai tunnel based on a physical model testrdquo ColdRegions Science and Technology vol 124 pp 54ndash66 2016

[19] X Zhang Z Zhou J Li Y Zhou and F Han ldquoA physicalmodel experiment for investigating into temperature redis-tribution in surrounding rock of permafrost tunnelrdquo ColdRegions Science and Technology vol 151 pp 47ndash52 2018

[20] Y Zeng K Liu X Zhou and L Fan ldquoTunnel temperaturefields analysis under the couple effect of convection-con-duction in cold regionsrdquo Applied =ermal Engineeringvol 120 pp 378ndash392 2017

[21] L Liu Z Li X Liu and Y Li ldquoFrost front research of a cold-region tunnel considering ventilation based on a physicalmodel testrdquo Tunnelling and Underground Space Technologyvol 77 pp 261ndash279 2018

[22] G Zhang Y Guo Y Zhou et al ldquoExperimental study on thethermal performance of tunnel lining GHE under ground-water flowrdquo Applied =ermal Engineering vol 106 pp 784ndash795 2016

[23] G Zhang S Liu X Zhao et al ldquo-e coupling effect ofventilation and groundwater flow on the thermal performance

Advances in Civil Engineering 13

of tunnel lining GHEsrdquoApplied=ermal Engineering vol 112pp 595ndash605 2017

[24] Q Hu R Shi Y Hu et al ldquoMethod to evaluate the safety oftunnels through steeply inclined strata in cold regions basedon the sidewall frost heave modelrdquo Journal of Performance ofConstructed Facilities vol 32 2018

[25] H Cai P Li and Z Wu ldquoModel test of liquid nitrogenfreezing-temperature field of improved plastic freezing piperdquoJournal of Cold Regions Engineering vol 34 no 1 2020

[26] S E A Gehlin and G Hellstrom ldquoInfluence on thermalresponse test by groundwater flow in vertical fractures in hardrockrdquo Renewable Energy vol 28 no 14 pp 2221ndash2238 2003

14 Advances in Civil Engineering

velocity -is antifreezing capability should be fully utilized inthe antifreezing design of cold region tunnels

4 Conclusions

A systematic study on the temperature field of cold regiontunnels is presented in which a model test that considers thecoupling effects of groundwater seepage and tunnel venti-lation is conducted -e effects of groundwater seepage onthe air temperature in the tunnel the surrounding rocktemperature the temperature at the interface between thelining and surrounding rock and the freezing damage of thetunnel in cold regions are studied -e following four mainconclusions are drawn

First groundwater seepage has a significant effect on theair temperature in the tunnel -e higher the groundwater

seepage velocity the higher the air temperature in thetunnel Groundwater seepage has a significant influence onthe thickness and length of the tunnel insulation layer in coldregions -e thickness and length of the tunnel insulationlayer can decrease under groundwater seepage

Second groundwater seepage and tunnel ventilationhave a coupling effect on the surrounding rock temperatureHigher groundwater seepage velocity and lower wind speedlead to higher surrounding rock temperature -e influenceof groundwater seepage and tunnel ventilation on thesurrounding rock temperature field is related to the depth ofthe surrounding rock

-ird groundwater seepage leads to an uneven tem-perature distribution at the interface between the lining andsurrounding rock -e tunnel ventilation further enhancesthis uneven temperature distribution -e groundwater

TS3-TS5TS3-TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3

TS5

TS6

45deg 18cm

ndash1

0

1

2

3

4

5

6

7

8

9

05 10 15 20 25 3000Groundwater seepage velocity (md)

(a)

TS3-TS5TS3-TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3

TS5

TS6

45deg 18cm

ndash1

0

1

2

3

4

5

6

7

8

9

05 10 15 20 25 3000Groundwater seepage velocity (md)

(b)

TS3-TS5TS3-TS6

Groundwater seepage

Tem

pera

ture

dro

p (deg

C)

TA

TS3

TS5

TS6

45deg 18cm

ndash1

0

1

2

3

4

5

6

7

8

9

05 10 15 20 25 3000Groundwater seepage velocity (md)

(c)

Figure 10 Relationships between the temperature differences at TS5 TS6 and TS3 and groundwater seepage velocity Average wind speedof (a) 0606ms (b) 1002ms and (c) 2398ms

12 Advances in Civil Engineering

seepage and tunnel ventilation have a coupling effect on theinterface temperature -is coupling effect is related to theinterface location -e influence of the groundwater seepagevelocity on the interface temperature has a spatial difference-e shape and size of the cross section of the tunnel have asignificant influence on the interface temperature undergroundwater seepage

Fourth cold region tunnels have an antifreezing capa-bility that is mainly related to the frost heaving of thesurrounding rock and the groundwater seepage velocity-eantifreezing capability of the tunnel should be fully utilizedin the antifreezing design of cold region tunnels

Data Availability

-e data used to support the findings of this study areavailable from the corresponding author upon request

Conflicts of Interest

-e authors declare that they have no conflicts of interest

Acknowledgments

-is study was supported by the Key Laboratory of Geo-technical and Underground Engineering of Ministry ofEducation Tongji University (No KLE-TJGE-B1605) theKey Laboratory of Rock Mechanics and Geohazards ofZhejiang Province (No ZJRM-2018-Y-01) and the SichuanScience and Technology Program (No 2018GZ0359)

References

[1] S Li M Zhang W Pei and Y Lai ldquoExperimental and nu-merical simulations on heat-water-mechanics interactionmechanism in a freezing soilrdquo Applied =ermal Engineeringvol 132 pp 209ndash220 2018

[2] S Li M Zhang Y Tian W Pei and H Zhong ldquoExperimentaland numerical investigations on frost damage mechanism of acanal in cold regionsrdquo Cold Regions Science and Technologyvol 116 pp 1ndash11 2015

[3] S Shen C Xia J Huang and Y Li ldquoInfluence of seasonal meltlayer depth on the stability of surrounding rock in permafrostregions based on the measurementrdquoNatural Hazards vol 75no 3 pp 2545ndash2557 2015

[4] K-J Jun Y-C Hwang and C-Y Yune ldquoField measurementof temperature inside tunnel in winter in Gangwon KoreardquoCold Regions Science and Technology vol 143 pp 32ndash42 2017

[5] Q Ma X Luo Y Lai F Niu and J Gao ldquoNumerical in-vestigation on thermal insulation layer of a tunnel in sea-sonally frozen regionsrdquoApplied=ermal Engineering vol 138pp 280ndash291 2018

[6] X Zhao X Yang H Zhang H Lai and X Wang ldquoAnanalytical solution for frost heave force by the multifactor ofcoupled heat and moisture transfer in cold-region tunnelsrdquoCold Regions Science and Technology vol 175 2020

[7] Y M Lai S Y Liu Z W Wu and W Yu ldquoApproximateanalytical solution for temperature fields in cold regionscircular tunnelsrdquoCold Regions Science and Technology vol 34no 1 pp 43ndash49 2002

[8] G Zhang C Xia M Sun Y Zou and S Xiao ldquoA new modeland analytical solution for the heat conduction of tunnel

lining ground heat exchangersrdquo Cold Regions Science andTechnology vol 88 pp 59ndash66 2013

[9] Y M Lai Z W Wu Y L Zhu and L N Zhu ldquoNonlinearanalysis for the coupled problem of temperature seepage andstress fields in cold-region tunnelsrdquo Tunnelling and Under-ground Space Technology vol 13 no 4 pp 435ndash440 1998

[10] X Zhang J Xiao Y Zhang et al ldquoStudy of the function of theinsulation layer for treating water leakage in permafrosttunnelsrdquo Applied =ermal Engineering vol 27 no 2-3pp 637ndash645 2007

[11] X Zhang Y Lai W Yu and S Zhang ldquoNon-linear analysisfor the freezing-thawing situation of the rock surrounding thetunnel in cold regions under the conditions of differentconstruction seasons initial temperatures and insulationsrdquoTunnelling and Underground Space Technology vol 17 no 3pp 315ndash325 2002

[12] X Zhang Y Lai W Yu and Y Wu ldquoForecast analysis for there-frozen of Feng Huoshan permafrost tunnel on Qing-Zangrailwayrdquo Tunnelling and Underground Space Technologyvol 19 no 1 pp 45ndash56 2004

[13] X Tan W Chen H Tian and J Cao ldquoWater flow and heattransport including icewater phase change in porous medianumerical simulation and applicationrdquo Cold Regions Scienceand Technology vol 68 no 1-2 pp 74ndash84 2011

[14] X Tan W Chen G Wu and J Yang ldquoNumerical simulationsof heat transfer with ice-water phase change occurring inporous media and application to a cold-region tunnelrdquoTunnelling and Underground Space Technology vol 38pp 170ndash179 2013

[15] X Tan W Chen D Yang et al ldquoStudy on the influence ofairflow on the temperature of the surrounding rock in a coldregion tunnel and its application to insulation layer designrdquoApplied =ermal Engineering vol 67 no 1-2 pp 320ndash3342014

[16] S Li F Niu Y Lai W Pei and W Yu ldquoOptimal design ofthermal insulation layer of a tunnel in permafrost regionsbased on coupled heat-water simulationrdquo Applied =ermalEngineering vol 110 pp 1264ndash1273 2017

[17] Q Yan B Li Y Zhang J Yan and C Zhang ldquoNumericalinvestigation of heat-insulating layers in a cold region tunneltaking into account airflow and heat transferrdquo Applied Sci-ences vol 7 no 7 p 679 2017

[18] Q Feng B-S Jiang Q Zhang and G Wang ldquoReliabilityresearch on the 5-cm-thick insulation layer used in theYuximolegai tunnel based on a physical model testrdquo ColdRegions Science and Technology vol 124 pp 54ndash66 2016

[19] X Zhang Z Zhou J Li Y Zhou and F Han ldquoA physicalmodel experiment for investigating into temperature redis-tribution in surrounding rock of permafrost tunnelrdquo ColdRegions Science and Technology vol 151 pp 47ndash52 2018

[20] Y Zeng K Liu X Zhou and L Fan ldquoTunnel temperaturefields analysis under the couple effect of convection-con-duction in cold regionsrdquo Applied =ermal Engineeringvol 120 pp 378ndash392 2017

[21] L Liu Z Li X Liu and Y Li ldquoFrost front research of a cold-region tunnel considering ventilation based on a physicalmodel testrdquo Tunnelling and Underground Space Technologyvol 77 pp 261ndash279 2018

[22] G Zhang Y Guo Y Zhou et al ldquoExperimental study on thethermal performance of tunnel lining GHE under ground-water flowrdquo Applied =ermal Engineering vol 106 pp 784ndash795 2016

[23] G Zhang S Liu X Zhao et al ldquo-e coupling effect ofventilation and groundwater flow on the thermal performance

Advances in Civil Engineering 13

of tunnel lining GHEsrdquoApplied=ermal Engineering vol 112pp 595ndash605 2017

[24] Q Hu R Shi Y Hu et al ldquoMethod to evaluate the safety oftunnels through steeply inclined strata in cold regions basedon the sidewall frost heave modelrdquo Journal of Performance ofConstructed Facilities vol 32 2018

[25] H Cai P Li and Z Wu ldquoModel test of liquid nitrogenfreezing-temperature field of improved plastic freezing piperdquoJournal of Cold Regions Engineering vol 34 no 1 2020

[26] S E A Gehlin and G Hellstrom ldquoInfluence on thermalresponse test by groundwater flow in vertical fractures in hardrockrdquo Renewable Energy vol 28 no 14 pp 2221ndash2238 2003

14 Advances in Civil Engineering

seepage and tunnel ventilation have a coupling effect on theinterface temperature -is coupling effect is related to theinterface location -e influence of the groundwater seepagevelocity on the interface temperature has a spatial difference-e shape and size of the cross section of the tunnel have asignificant influence on the interface temperature undergroundwater seepage

Fourth cold region tunnels have an antifreezing capa-bility that is mainly related to the frost heaving of thesurrounding rock and the groundwater seepage velocity-eantifreezing capability of the tunnel should be fully utilizedin the antifreezing design of cold region tunnels

Data Availability

-e data used to support the findings of this study areavailable from the corresponding author upon request

Conflicts of Interest

-e authors declare that they have no conflicts of interest

Acknowledgments

-is study was supported by the Key Laboratory of Geo-technical and Underground Engineering of Ministry ofEducation Tongji University (No KLE-TJGE-B1605) theKey Laboratory of Rock Mechanics and Geohazards ofZhejiang Province (No ZJRM-2018-Y-01) and the SichuanScience and Technology Program (No 2018GZ0359)

References

[1] S Li M Zhang W Pei and Y Lai ldquoExperimental and nu-merical simulations on heat-water-mechanics interactionmechanism in a freezing soilrdquo Applied =ermal Engineeringvol 132 pp 209ndash220 2018

[2] S Li M Zhang Y Tian W Pei and H Zhong ldquoExperimentaland numerical investigations on frost damage mechanism of acanal in cold regionsrdquo Cold Regions Science and Technologyvol 116 pp 1ndash11 2015

[3] S Shen C Xia J Huang and Y Li ldquoInfluence of seasonal meltlayer depth on the stability of surrounding rock in permafrostregions based on the measurementrdquoNatural Hazards vol 75no 3 pp 2545ndash2557 2015

[4] K-J Jun Y-C Hwang and C-Y Yune ldquoField measurementof temperature inside tunnel in winter in Gangwon KoreardquoCold Regions Science and Technology vol 143 pp 32ndash42 2017

[5] Q Ma X Luo Y Lai F Niu and J Gao ldquoNumerical in-vestigation on thermal insulation layer of a tunnel in sea-sonally frozen regionsrdquoApplied=ermal Engineering vol 138pp 280ndash291 2018

[6] X Zhao X Yang H Zhang H Lai and X Wang ldquoAnanalytical solution for frost heave force by the multifactor ofcoupled heat and moisture transfer in cold-region tunnelsrdquoCold Regions Science and Technology vol 175 2020

[7] Y M Lai S Y Liu Z W Wu and W Yu ldquoApproximateanalytical solution for temperature fields in cold regionscircular tunnelsrdquoCold Regions Science and Technology vol 34no 1 pp 43ndash49 2002

[8] G Zhang C Xia M Sun Y Zou and S Xiao ldquoA new modeland analytical solution for the heat conduction of tunnel

lining ground heat exchangersrdquo Cold Regions Science andTechnology vol 88 pp 59ndash66 2013

[9] Y M Lai Z W Wu Y L Zhu and L N Zhu ldquoNonlinearanalysis for the coupled problem of temperature seepage andstress fields in cold-region tunnelsrdquo Tunnelling and Under-ground Space Technology vol 13 no 4 pp 435ndash440 1998

[10] X Zhang J Xiao Y Zhang et al ldquoStudy of the function of theinsulation layer for treating water leakage in permafrosttunnelsrdquo Applied =ermal Engineering vol 27 no 2-3pp 637ndash645 2007

[11] X Zhang Y Lai W Yu and S Zhang ldquoNon-linear analysisfor the freezing-thawing situation of the rock surrounding thetunnel in cold regions under the conditions of differentconstruction seasons initial temperatures and insulationsrdquoTunnelling and Underground Space Technology vol 17 no 3pp 315ndash325 2002

[12] X Zhang Y Lai W Yu and Y Wu ldquoForecast analysis for there-frozen of Feng Huoshan permafrost tunnel on Qing-Zangrailwayrdquo Tunnelling and Underground Space Technologyvol 19 no 1 pp 45ndash56 2004

[13] X Tan W Chen H Tian and J Cao ldquoWater flow and heattransport including icewater phase change in porous medianumerical simulation and applicationrdquo Cold Regions Scienceand Technology vol 68 no 1-2 pp 74ndash84 2011

[14] X Tan W Chen G Wu and J Yang ldquoNumerical simulationsof heat transfer with ice-water phase change occurring inporous media and application to a cold-region tunnelrdquoTunnelling and Underground Space Technology vol 38pp 170ndash179 2013

[15] X Tan W Chen D Yang et al ldquoStudy on the influence ofairflow on the temperature of the surrounding rock in a coldregion tunnel and its application to insulation layer designrdquoApplied =ermal Engineering vol 67 no 1-2 pp 320ndash3342014

[16] S Li F Niu Y Lai W Pei and W Yu ldquoOptimal design ofthermal insulation layer of a tunnel in permafrost regionsbased on coupled heat-water simulationrdquo Applied =ermalEngineering vol 110 pp 1264ndash1273 2017

[17] Q Yan B Li Y Zhang J Yan and C Zhang ldquoNumericalinvestigation of heat-insulating layers in a cold region tunneltaking into account airflow and heat transferrdquo Applied Sci-ences vol 7 no 7 p 679 2017

[18] Q Feng B-S Jiang Q Zhang and G Wang ldquoReliabilityresearch on the 5-cm-thick insulation layer used in theYuximolegai tunnel based on a physical model testrdquo ColdRegions Science and Technology vol 124 pp 54ndash66 2016

[19] X Zhang Z Zhou J Li Y Zhou and F Han ldquoA physicalmodel experiment for investigating into temperature redis-tribution in surrounding rock of permafrost tunnelrdquo ColdRegions Science and Technology vol 151 pp 47ndash52 2018

[20] Y Zeng K Liu X Zhou and L Fan ldquoTunnel temperaturefields analysis under the couple effect of convection-con-duction in cold regionsrdquo Applied =ermal Engineeringvol 120 pp 378ndash392 2017

[21] L Liu Z Li X Liu and Y Li ldquoFrost front research of a cold-region tunnel considering ventilation based on a physicalmodel testrdquo Tunnelling and Underground Space Technologyvol 77 pp 261ndash279 2018

[22] G Zhang Y Guo Y Zhou et al ldquoExperimental study on thethermal performance of tunnel lining GHE under ground-water flowrdquo Applied =ermal Engineering vol 106 pp 784ndash795 2016

[23] G Zhang S Liu X Zhao et al ldquo-e coupling effect ofventilation and groundwater flow on the thermal performance

Advances in Civil Engineering 13

of tunnel lining GHEsrdquoApplied=ermal Engineering vol 112pp 595ndash605 2017

[24] Q Hu R Shi Y Hu et al ldquoMethod to evaluate the safety oftunnels through steeply inclined strata in cold regions basedon the sidewall frost heave modelrdquo Journal of Performance ofConstructed Facilities vol 32 2018

[25] H Cai P Li and Z Wu ldquoModel test of liquid nitrogenfreezing-temperature field of improved plastic freezing piperdquoJournal of Cold Regions Engineering vol 34 no 1 2020

[26] S E A Gehlin and G Hellstrom ldquoInfluence on thermalresponse test by groundwater flow in vertical fractures in hardrockrdquo Renewable Energy vol 28 no 14 pp 2221ndash2238 2003

14 Advances in Civil Engineering

of tunnel lining GHEsrdquoApplied=ermal Engineering vol 112pp 595ndash605 2017

[24] Q Hu R Shi Y Hu et al ldquoMethod to evaluate the safety oftunnels through steeply inclined strata in cold regions basedon the sidewall frost heave modelrdquo Journal of Performance ofConstructed Facilities vol 32 2018

[25] H Cai P Li and Z Wu ldquoModel test of liquid nitrogenfreezing-temperature field of improved plastic freezing piperdquoJournal of Cold Regions Engineering vol 34 no 1 2020

[26] S E A Gehlin and G Hellstrom ldquoInfluence on thermalresponse test by groundwater flow in vertical fractures in hardrockrdquo Renewable Energy vol 28 no 14 pp 2221ndash2238 2003

14 Advances in Civil Engineering