China Rail Tunnels

Development of Railway Tunneling Technology in China

He Huawu

2006.11.20

contents

● Introduction to current situation of China’s railway and

eleventh Five-year Plan

● Overview of China’s railway tunnels

● Development in the construction technology of tunnels in operation

● Overview of the tunnels under construction and the key technology

● Overview of the tunnels in planning and the new technology to be used

● Innovation in the construction technology of China’s railway tunnels

Introduction to current situation of China’s railway and eleventh Five-year Plan

Current situation of China’s railway

By the end of year 2005, operational

mileage of railways in China was 75,400 km;

In 2005, China's railways transported 1.156

billion passengers and 2.693 billion tons of

goods;

Passenger transportation volume was 606.2

billion passengers-km, freight

transportation volume was 2072.6 billion

ton– km.

Eleventh Five-year Plan

According to the Eleventh Five-year Plan, new lines with the length of 17,000 km are to be constructed, including 7,000 km passenger-dedicated lines. Also in the plan are 8,000 km existing double lines and electrification reconstruction of 15,000 km existing lines. In 2010, operation mileage of railway nationwide will reach more than 90,000 km. And the rate of double lines and electrificated lines will be above 45 %.

The overall length of high-speed passenger railway network will be more than 20,000 km, and the total capacity of coal transport corridor will reach 1.8 billion tons. The railway network in the west will be 35,000 km long. And a container transport system covering the whole nation will be created.

Eleventh Five-year Plan

Overview

Overview of China’s railway tunnels

Overview

According to statistics, by the end of 2005, 7,538 railway tunnels with the tota Length of 4,314 km were built in China, being No.1 in the world.

In 2006, 1,785 tunnels, 2,164 km in total length, are being constructed. Around 146 PDL tunnels with total length of 184 km are to be built.

Railway tunnels on passenger-goods mixed lines in planning are about 2,100 km, among which extra-long tunnels amount to 760 km.

Overview

This group of vivid figures indicate the glorious past of China’s railway tunnels and the bright future for its development .

Tunnels in operation

Development in the construction technology of tunnels in operation

An overview of tunnels in operation Tunnels in operation

By the end of 2005, 7,538 railway tunnels with the total length

of 4,314 km had been built in China, ranking No.1 in the world.

The number of the finished tunnels



The accumulated number of the finished tunnels

Number

Length(km)

Tunnels in operationDevelopment in the construction technology of railway tunnels

Shi Qiuling-—the earliest tunnel in China, built in 1890

From Qing Dynasty to today, the construction of railway tunnels has gone through a period of 120 years. Its construction technology has been greatly improved.

Optical theodolite

Tunnel control measurement, from the use of optical theodolite to that of electro-optical distance measuring instrument.

Electro-optical distance measuring instrument

Development in the construction technology of railway tunnels Tunnels in operation


Application of GPS

At present, GPS

technology

is widely used.


Geological surveyfrom simple drilling to remote sensing, physical survey and comprehensive exploration.


The method for classification of surrounding rocks has shifted from soil-rock classification and the classification method based on coefficient of ground solidness, to the classification method based on stability of surrounding rocks and then finally to the classified categorization of surrounding rock.


Design tool has

evolved from manual

calculation and

manual drawing to

the widely-used CAD

technology.


Construction method has developed from traditional excavation method, pre-pilot tunnel method, sequential method to the New Austria Tunneling Method which gives full play to self-supporting function of the surrounding rocks, integrate surrounding rocks and support work as a whole to ensure the stability of the tunnel.


Construction technology advances from maunal operation, construction with small sized machines to matched mechanized production line including drilling, mucking, shotcrete-anchor supporting, lining casting.

Tunnels in operation

The application of TBM

in the 1990s facilitated

the advancement from

manual operation to the

industrialization of the

tunnel construction.


Construction standard has also been enhanced with the technical improvements in preliminary support, concrete lining, water-proof and drainage, under-rail structure, disaster prevention and rescue, ventilation and lighting and so on.

Tunnel lining


Da Yaoshan Tunnel in Hengyang-Guangzhou section of Beijing-Guangzhou railway, with length of 14,294m long, is the longest electrified double-track tunnel built in China.

Da Yaoshan Tunnel


Da Yaoshan Tunnel started construction in August, 1981 and opened to operation in December, 1988.

Da Yaoshan Tunnel


Main results achived in Da Yaoshan tunnel

The composite lining with a PVC water-proofing layer between primary support and permanent lining was used as the main tunnel structure .

Large machines were used to establish production lines, including drilling&blasting, loading&transporting, shotcrete&anchoring and second lining casting.

To overcome the No.9 fault, a whole set of technoligies were applied, including drainaging and pressrue-releasing with parallel pilot, geological forecast and pre-grouting from shallow holes,etc.

Maximum tunnel completion length per year:4245m; Maximum tunnel completion length per month at one heading:218m;maximum excavation length per month at one heading:205m;maximum lining casting length per month at one heading:303m.


Da Yaoshan Tunnel is a succesful example of applying

NATM principle in China’s tunneling practice, and a

milestone in the history of China’s tunnel construction

due to new developments of reseach, design,constrcution

technologies achived in this tunnel.


Qinling Tunnel is

two parallel single-

track one with a

length of 18,456 m,

It's the longest

railway tunnel built

in China in the last

century.


TubeⅠof QinlingTunnel is excavated by one TBM in the north and south sections respectively. For Tube Ⅱ, a pilot tunnel is constructed for geographical exploration of Tube Ⅰand then is enlarged into TubeⅡ. The records of excavation for TubeⅠ: in the north section , 40.5 m per day, 528.1 m per month, and in the south section, 35.2 m per day, 509 m per month.


The records for drilling and blasting construction of the pilot tunnel in Tube Ⅱ: in the north section, 456 m per month and in the south section, 426 m/month. Average advance speed for pilot tunnel is 250 m per month for one heading.


During construction of Qinling Tunnel, a series of research projects on construction technologies, geology, ventilation and cooling, elastic track bed, maintenance in operation, environmental protection solved many problems in design and construction.


Under the guidance of the principles of “high starting point, high standard, high speed, high profit; scientific decision-making, normalized construction, standardized operation and modernized management”, the design and construction of Qinling Tunnel demonstrate the progress of China’s tunnelling technologies from drilling and blasting construction to open TBM construction, indicating that China has headed to the top group of the world in the technology of railway tunnel mechanized construction. QinlingTunnel is a milestone in the history of China’s tunnel construction at the end of 20th century.


Wushaoling Tunnel in

the newly -built second

line of Lanzhou-Xinjiang

Railway has a length of

20,050m. It consists of

two single-track tubes,

with a distance of 40 m

between them.


The construction of Wushaoling Tunnel started in March of 2003, and the No.1 and No.2 tube were put into operation on March 30th and August 12th of 2006 respectively.


The tunnel created a new record in speed for single-track tunnel construction in China.The tunnel was a breakthrough in constructing tunnel in soft rock with deep overburden and complex geology.


1,338 m-long Fenghuoshan Tunnel in Qinghai-Tibet Railway was built in permanent frozen soil at the highest altitude in the world. The altitude at the top of mountain is 4995 m above sea level, and the altitude of the track is 4905 m above sea level. The thickness of permanent frozen soil is 80 to 100 m in the tunnel section.


1,686 m-long Kunlunshan Tunnel in Qinghai-Tibet Railway is the longest tunnel in permanent frozen soil in the world. The construction of the tunnel started in September 2001 and the excavation finished in September 2002.


The two tunnels mentioned above are typical tunnels constructed under the conditions of frozen soil, low oxygen, and adverse natural environment in Qinhai-Xizang area where partial pressure of oxygen is below the limit condition for life. New technologies including two-layer cast concrete, multiple waterproof measures, heat insulation measures, early-setting watertight concrete with high durability for low temperature, air-conditioning in tunnel and oxygen provision at work face were utilized in the design and construction. China's construction technologies of tunnels in plateau frozen soil has been greatly developed.

Overview of tunnels under constrcution

Tunnels under constrcution

Overview of the tunnels under construction and the key technology



Railway tunnels under construction include tunnels on passenger dedicated lines (including high speed railways and inter-city railways) and tunnels on passenger-freight mixed transportation lines. By October of 2006, there are 516 PDL tunnels under construction, with a total length of 708 km.



Around 1,269 tunnels with a total length of 1,456 km on passenger-freight railway lines are under construction, and around 146 tunnels with a total length of 184km are to be constructed soon.



An overview of PDL Tunnels under construction in 2006 Number

Length/km



An overview of PDL tunnels to be constructedNumber

Length/km



Length/km

Number

An overview of tunnels on passenger-freight railways in 2006---Part 1



An overview of tunnels on passenger-freight railways in 2006---Part 2

Number

Length/km


The main difference between tunnels on high speed railways and those on normal railways lies in the obviously negative influence of aero-dynamics effect on train running, passengers’ comfortable feeling, train-related performance and the environmental condition at the portal (traveling resistance, transient pressure, mirco pressure wave, wind) caused by train passing through tunnel. All these are the key problems to be solved in the design of high speed railways.

Key technologies of high speed railway tunnels


Determine the appropriate effective clearance area

Decide on the proper support and lining design parameters

Set up the reliable safety system for operation

Adopt the favorable portal shape to reduce the aero-dynamics effect




Taihangshan Tunnel is the longest tunnel on Shijiazhuang-Taiyuan PDL, and also the longest railway mountain tunnel under construction in China at present.



View of the entry and exit of Taihangshan Tunnel

Taihangshan Tunnel



Dyaoshan tunnel group on WuguangPDL is consisted of Dayaoshan 1, Dayaoshan 2, and Dayaoshan 3 tunnels, going through Nanling Mountainous area. The lengths of the three tunnels are 10,081m and 6,024m and 8, 387 m respectively.

Three tunnels are all double-track tunnels. The distance between tracks is 5m, the designed highest speed is 350 km/h and the effective area of clearance profile is 100 m2.



Shiziyang Tunnel is situated between Dongyong Station and Humen Station on the Guangzhou-Shengzheng-Hongkong PDL. The tunnel is 10.8 km long.



Shiziyang Tunnel goes through under Zhujiang River,and is the first underwater railway tunnel in China.



There are in total 23 cross passages connecting the tunnels, of which 19 are located in the sections excavated by 4 slurry shield machines.



Hanguguan Tunnel on Zhengzhou-Xian PDL with a total length of 7,851 m, and a maximum depth of 220 m, is the longest and biggest tunnel in loess.



No.3 inclined shaft of HanguguanTunnel is under construction.



Liuyanghe Tunnel on Wuguang PDL is located in the east of Changsha City in Hunan Province, running down below the JingzhuFreeway and XingshaDevelopment Zone, Liuyang River and airport speedway in Changsha City. The tunnel is as long as 9,920 m.



There are altogether 3 shafts and 1 inclined shaft in Liuyanghe Tunnel.



View of Liuyanghe Tunnel


Among 1,456 km-long tunnels on the passenger-freight mixed railway, there are 10 extra-long ones, having length of about 128 km.

● The longest tunnel is the 20,780m long Luliangshan Tunnel on DazhongyingRailway.

● The tunnels in the most complicated geological area are karst tunnels on Yiwan Railway

● The tunnels containing most gas are Yunding, Tiantaisi Tunnels on Dacheng Railway.

● The longest railway tunnel powered by internal combustion is Nanshan Tunnel on Baihe-Helong section of the railway passage in the east of Northeastern China. It has the length of 7595m.

.

The Key Technology● The geological forecast during the construction

● Alarming technology against geological disasters.

Key technologies of passenger-freight mixed railway



● Use the comprehensive geological forecast technology in the construction of geologically complicated tunnels, and make it part of the procedure in construction management.

● The commonly used geological forecast methods are geological survey, geological mapping at the face, seismic reflection, georadar, HSP, high-frequency seismic reflection.



● Anti-disaster warning technology is applied to prevent the geological disasters such as water inflow and collapse of karst tunnels and other geologically complicated tunnels to avoid the casualty and loss of equipment during the construction.

● The warning system in the construction of complex karst tunnel consists of six parts: light and sound warning, communication in emergent case, TV monitor, escape passage, exit signs, emergent lighting, escape equipment, and emergent drainage.



Yiwan Railway is 378km long in total. The length of tunnels on railway line amounts up to 230 km and the proportion of tunnels to lines reaches as high as 60%.



Karst geology in Tunnels on Yiwan railway is highly developed.

The eight most risky tunnels are

● Baziling (5,867m)

● Yesanguan (13,833m)

● Dazhiping (8,770m)

● Yunwushan (6, 640m)

● Malujing (7,879m)

● Jingzishan (6,835m)

● Qiyueshan (10,528m)

● Bieyancao (3,721m)



Big karst cavern in Wuzhuaguan Tunnel



Luliangshan Tunnel, 20,780 m in total length, is the longest tunnel on Taizhong Railway. It is designed to be the double tube and single track tunnel. The distance between tracks is 30m, and the designed speed is no less than 200km/h.



The construction site in the Luliangshan Tunnel

Tunnels in planning

Overview of tunnel in planning and the new technology to be adopted

Overview of tunnels in planning

Tunnels in planning

According to statistics, the total length of railway tunnels to be constructed in the next five to ten years will exceed 2500km. At present, tunnels to be constructed and being designed have exceeded 2100km, including about 760km long extra-long tunnels , which exceed one third of the total length of tunnels to be constructed in the planning.

Main techniques adopted in planned tunnels

Tunnels in planning

Railway tunnels to be constructed in planning

The lines with tunnels longer than 100km are Lanzhou-Chongqin railway﹑Xiangtang-Putian railway ﹑ Dali-Ruili railway ﹑ Baotou-Xi’an railway and Lichuan-Peilin railway, etc.. The longest tunnel planned to be constructed is the 32.6 km-long Guanjiao tunnel in Xining-Ge’ermu section along the Tibetan line, where a second line will be built.

Tunnels in planningMain techniques adopted in planned tunnels

● The construction technology of TBM

● The rapid construction technology of long and extra-long tunnels

● Comprehensive technology of geographical exploration

● The technology of construction ventilation and operation ventilation

Tunnels in planningMain techniques adopted in planned tunnels

Guanjiao Tunnel in Xining-GeErmu section along the Tibetan line, where a second line will be built, is a tunnel that goes though the South Mountain in Qinghai. It is designed to be about 32.6km long, and will be the longest tunnel in planning in China up till now.


Guanjiao Tunnel adopts a concept of parallel two single-track tunnels, with a distance of about 40m between tracks. The sea level at the entrance of the tunnel is about 3380m, 300m and more lower than that of existing GuanjiaoTunnel.


Tunnels in planning

The tunnel is planned to adopt a construction method that combines TBM and D&B, using D&B for the construction in geologically complex section before the whole tunnel construction starts, so as to ensure the effective construction of TBM.


Tunnels in planning

The main line of Xiangpu railway, from Xiangtang to Putian, is about 607km. There are altogether 114 tunnels along the whole line, amounting up to about 290km in total length.


Tunnels in planning

There are 11 tunnels longer than 10km in Xiangpu railway, with a total length of 176km, among which three tunnels exceed 20km. The longest tunnel is the Dai Yunshan tunnel, which is about 27.8km long.


Tunnels in planning

Dai Yunshan tunnel﹑ Gao Gaishan tunnel﹑ Qing Yunshantunnel and Xue Fengshan tunnel, which are longer than 15km on the Xiangpu railway, adopt the concept of double tube and single track, with the rest all adopting the single tube and double track in one tube. The designed running speed in the tubes will not be lower than 200km/h.


Tunnels in planning

In the preliminary scheme of Lanyu railway, 117 tunnels in total length of about 480km will be constructed, accounting for more than 60% of the total length of the railway. In the section from Lanzhou to Guangyuan, there will be 66 tunnels with a total length of about 370 km.And there are 12 extra-long tunnels with a total length of about 190km. The longest tunnel is the Xi Qingling tunnel, which is about 29710m long.

Push forward the innovation and development of tunnel construction technology of China’s railways

The innovation in the construction technology of China railway tunnels


The practical guiding principles for vigorous technological innovation in the railway tunnel construction of China are:

Sticking to the scientific development principle, building up transportation-serving and human-orientated design concept, intensifying efforts in scientific innovation and self-creation, to greatly promote the progress of China’s railway tunnel technology.


I. Promote the development of urban tunnel and underwater tunnel technology.

Tunnels going under the urban areas have a series of advantages: it can reduce dismantle and relocation in urban area and the anticipated noise pollution caused by railways to buildings, and at the same time it can promote harmonious development between railways and cities. Railways, with tunnels , could transcend oceans and rivers, and thus have obvious advantages in terms of watercourse environmental protection, navigations and all-day operation of trains. In the future railway construction, vigorous efforts should be made to promote urban tunnel and underwater tunnel technologies.


II. Improve tunnel mechanization construction capacity, and relieve labor intensity.

To achieve modernization of tunnel project, we must realize modernization of main procedures in construction, develop specialized equipments suitable for China’s tunnel operation, and adopt the TBM method by preference for some extra-long tunnels in the future. We also need to adopt the complete set of mechanized construction methods for other long and extra-long tunnels, develop small-sized equipments suitable for concrete spray, steel arch installation, waterproof membranes laying, drilling and grouting etc. for instance.


III. Enhance the water-proof and drainage technology for tunnels and lessen damage to tunnels.

We shall have reasonable water-proof and drainage designs, guarantee the quality of water-proof and drainage materials, and further improve craftsmanship of water-proof and drainage system. Besides, we shall also actively promote the application of maintainable water-proof and drainage systems and prevent railway tunnels from water seepage and leakage to lessen damage to tunnels.


IV. Promote informatization of tunnels, develop geographical forecast technology of tunnel construction, and develop on-site dynamic design and scientific construction management.


V. Systemize Tunnel Safety Measures

Nowadays, the disaster prevention system of railway tunnels in operation has not been fully developed. As an increasing number of high speed railway tunnels and extra-long tunnels are being constructed now, we should strength efforts in tunnel safety research to make the disaster prevention measures more systematic.


VI. Plan landscaping at tunnel portals.

In the construction of tunnels, the impact on the surrounding environment should be minimized through reducing the excavation of slope around the portal, protecting the vegetation and ecology of portal area and choosing simple portal structure, to harmonize the surroundings at the tunnel portals.


China has become a country with a great number of tunnels nowadays. Although we have accumulated rich experience in tunnel construction, we still lag behind some highly developed countries in terms of construction quality and technological capacity. We will explore persistently and try our best to make innovations by learning from overseas advanced technologies.

Specific guidelines for future development are as follows: sticking to the scientific development principle, building up transportation-serving and human-oriented design concept ,strengthening efforts in original innovation, collective innovation and re-innovation by absorbing overseas technologies, to push forward the technological advancement of railway tunnels in China.

Thank You!

Documents

China Rail Tunnels