Advances in Trenchless Technology

ADVANCES IN TRENCHLESS TECHNOLOGY

A TECHNICAL PAPER ON

Submitted By:

DARADE DHARMA KACHARU

B.E.(CIVIL)

VIKRAM K. KAMATH

B.E.(CIVIL)

Guided By:

Dr. ARUN KUMAR

H.O.D. (Civil Dept.)

0


CONTENTS

CHAPTER PAGE NO.

1] INTRODUCTION …………………………………………………….. 01

2] SCOPE.......................................................................................... 03

3] TECHNIQUES………………………………………………………….04

4] SAFETY MEASURE ……………………………………………………09

5] ADVANTAGES & DISADVANTAGES……………………………….11

6] COMPARATIVE STUDY………………………………………...........12

7] APPLICATION / USES………………………………………………...13

8] INDIAN USE…………………………………………………………….14

9] A CASE STUDY………………………………………………………..15

10] PHOTOGRAPHS………………………………………………………16

CONCLUSION…………………………………………………………18

BIBLIOGRAPHY……………………………………………………… 19

1


INTRODUCTION

Definition: - “Trenchless Technology” is an innovative process of installing and the

under-ground utilities like water sever and gas pipelines, electricity and communication

cables and other underground facilities. This technique minimizes and eliminates the need

for excavation of open cut –trenches. Some time it is also referred as ‘No Dig’ method. It is

an eco-friendly, hi-tech, speedy construction method for the future builders and the

construction industry in India.

History:- “Trenchless Technology” or “No dig Technology” is a comparative of recent

origin i.e. only 15-20 years old. Australia was one of the first countries to use this

technology later on Japan, Germany, U.S.A., U.K., etc used this technology. Trenchless

Technology has become an effective and economic alternative to traditional open cut

construction method’s followed in construction industry, particularly used in the laying and

rehabilitation of underground utilities which is mentioned above.

In India, this technology was introduced for the first time in Kolkata four year

back by Bose international, which is currently acting as technical adviser to Broadway

infrastructure. India offers a huge market for trenchless technology. Leading equipment

manufacturers from world over are eager to enter India in collaboration with Indian

partners. Our metropolitan cities viz.Delhi,Kolkata,Mumbai,Chennai&Bangalore& other

fast growing state capitals are congested have outgrown their master- plan limits

necessitating immediate need for rehabilitation, renovation, augmentation of existing old

water supply and sewer lines and also new installation . Lying of communication cables,

gas and oil pipelines and power cables is yet another area for adoption of the trencheles

technology which has already gained momentum in a substantial measure. There is some

special application too like construction of sub-ways, creating underground space, micro-

hydel power plants, recharging of underground water table, ore slurry transportation, etc.

Nowhere in the world where trenchless technology is adopted, have government issued any

legislation. Based on the inherent advantages, governments have only facilitated and

encouraged the industry to adopt the technology in their countries. The success story

2

CHAPTER 01


from Singapore shows how they introduced the technology just by banning digging off

open trenches across the road.

Potential market:-India is the most populous country in the world next only to

china. in spite of the planned economic growth, the urban centers/cities have been growing

population continuously migrating from rural areas to urban

areas.Delhi,Mumbai,Calcutta,Madras and Bangalore etc.have already reached their limit of

congestion,pollution,shortage of water supply, breakdown and blockages in city sewerage

systems calling for municipal/public health engineers to undertake immediate measures to

provide new or renovate and repair existing utility systems.Goverment of India has also

laid stress on immediate development of infrastructure. India is poised offer a huge market

for trenchless technology particularly for manufacture of equipment, materials and other

geotechinal equipment.It also offers growing employment opportunity for public health

engineers, technicians and semi- skilled workers all over India. Currently very few

engineers aware of the advantage of trenchless technology in India. As the awareness

grows, social costs evaluated the choice will be for trenchless technology from open cut

method.

3


CHAPTER NO.2

SCOPE

The aid of this article is to briefly discuss about the development and

management of the trenchless technology underground utilities infrastructure and to focus

attention of administrators,builders,engineers,academicians,consultants.Heads of civic-

bodies like municipal corporations, water and sewerage Boards ,state electricity boards,

Department of telecommunications, cable operators, ministry of surface transport, Ministry

of environment, engineering colleges etc.for its early adoption.

This article generally introduces and discusses various trenchless

technology methods being used for laying new underground utilities and rehabilitation of

age old and damaged underground utilities.

4


CHAPTER NO.3

TECHNIQUES

Techniques can be classified in two broad groups as follows,

1] New installation method

2] Rehabilitation & renovation of existing installations.

3.1 New installations: - New underground utilities like sewers, water supply pipe lines,

cables etc. are installed by methods like pipe jacking,Microtunnelling,moling,directional

/guided drilling, rod pushing etc.(table1).Equipment and material required is described in

the succeeding paragraphs. Associated with these are a number of essential geo-technical

services/surveys.

1.Pipe Jacking:-After the construction of jacking pit and the receiving pit, sufficient

number of hydraulic jacks were mobilized to site.(The push of the jack being 600 mm, 4

jacks were adopted to work in tandem)

Table 2:- New installation methods

Services Trenchless methods Diameter

●Sewers & water supply

pipelines

●Sewers/water pipelines

●Oil pipelines

●Gas pipelines

●cables

●Pipe jacking –

●Microtunnelling & pipe

jacking –

●Directional drilling –

●Guided drilling-

●Impact moling-

●Rod pushing-

(>1000mm)

(>250mm)

(>200mm)

(50mmto600mm)

(<300mm)

(<300mm)

2. Horizontal Directional Drilling:-It can be defined as drilling done along a predefined

profile by a drilling tool and pulling the product pipe along the already drilled hole.

It consist two stages:

Stage1:- It consists of drilling a small diameter pilot hole along the desired centerline of a

Proposed line.

Stage2:- Pilot hole is enlarged to the desired diameter to accommodate the utility line & to

pull the utility line through the enlarged hole. The pilot hole is of approximately 3inches

(75mm) in diameter &is drilled with a specially built rig up with an inclined carriage,

5


typically adjusted to between 5&30 degrees which pushes the drill rod in to the ground. As

the pilot hole is being drilled, bentonite drilling mud is pumped down the center of drill

rods.

3. Ramming: - In this method the pipe is rammed through the soil by using a device

attached to the end of the pipe to drive the pipe through the soil. In this method, the tool

does not create a bore hole. It acts as hammer to drive the pipe through the soil. it sufficient

room is available the bore pit is constructed so to enable the pipe to be driven as a single

unit in case of congest areas, the pipe is installed in segments of size depending of the bore

pits available.

The type of pipe installed by the ramming method is limited to

steel due to the application of cyclic impact loads on the pipe. The size of pipe installed by

this method ranges from 2 inches (50mm) to 55 inches(1400mm). This method is capable

off installing pipes to near 200 inches (60m) in length.

4. Auger boring:-

The auger horizontal earth boring processes of simultaneously

jacking casing through the earth while removing the spoil inside the encasement by means

of rotating flight auger. The auger is flighted tube having a dual function firstly it has

coupling at each end that transmits torque to the cutting head from the power source

located in the bore pit & secondly it serves to transfer spoil back to the machine. The

casing support the soil around it spoils is being removed. This method requires bore pits

both at the entry & exit points of the bore. The size of boring pits depends on the size &

length of casing pipe being used.

5. Impact Moling:-

This method requires the use of boring & receiving pits. The tool

is then removed & cable is attached to the air hose & pulled back through the bore hole.

When rigid pipe is to be installed the tool & air hose are removed & the pipe is push

through the open bore hole. Since the boring process is independent of the pipe insertion

process any type of pipe or cable can be installed in the bore hole by this method.

Table 3: Trenchless Rehabilitation Methods

Method DiameterRange (mm)

MaximumInstallation

(Meters)

Linear Materials Application

6


CIPP:a) Inserted in

placeb) Winched in

place

100-2700

100-1400

900

150

*Thermoset resin/fabric composite

*Thermoset resin/fabric composite

Gravity& pressure pipelinesGravity &pressure pipelines

Slip lining :a) segmentalb) continuousc) spiral

wound

100-4000100-1600100-2500

300300300

PE,PP,PVC PVC,PE,PP

PE, PVC, PP,PVDF

Gravity& pressure pipelinesGravity &pressure pipelinesGravity &pressure pipelines

Inline Replacement :a)Pipe displacementb) Pipe removal

100-600Up to 900

230100

PE,PP,PVCPE,PVC,PP

Gravity and pressure pipelines


Close Fit Pipe :a) Modified

cross sectionb) Draw downc) Roll down

100-400

62-60062-600

210

320320

HDPE,PVC,

HDPE, PVCHDPE,MDPE




Point Source Repair :

a) Robotics structural repair

b) Groutingc) Link-seald) Point CIPPe) Spray-on-

lining

270-760

N/A100-600100-60076-4500

N/A

N/AN/A15150

Epoxy resin/cement mortar

Chemical groutingSpecial sleeve

Fibre glass polyesterEpoxy resin/cement

mortar

Gravity

AnyAny

Gravity


M Manhole Rehabilitation

Any N/A Spray-on-lining, PVC,CIPP

Sewer manholes

3.2 HOW TO USE:

Rehabilitation & Renovation: - pipeline rehabilitation & renovation is a process of

improving the performance & extending the life of existing utility pipelines. The process

thus enhances the economic value of the utility pipeline. The improvement of performances

7


&extending the life span can be achieved by enhancing the structural, hydraulic &

environmental performance of the utility pipeline by various rehabilitation & renovation

methods, described hereinafter. Table-2 gives further highlights of Trenchless methods

adopted for rehabilitation & renovation of underground utilities.

Cured In Place Pipe (CIPP):- CIPP is liquid thermostat resin-saturated material that is

inserted in to the existing pipeline by hydrostatic or air inversion or mechanically pulling

with a winch and cable. The material is heat cured in place. (Example: In-situ form, In

pipe, In liner, etc.)

Slip Lining:-Slip lining is one of the earliest method pipeline rehabilitation. A new pipe of

smaller diameter is inserted by pulling or pushing in to deteriorated host pipe. The annular

space in between is grouted. This is a simple and inexpensive method but in this method

hydraulic capacity is reduced. Different methods in use are:

a) Continuous slip lining by HDPE pipes

b) Segmental lining by GRP:PVC,PE pipes

c) Spirally wound lining ,by helically winding a “T” ribbed plastic liner with

interlocking edges,eg.Rib Lock

In line replacement: when pipe lines are structurally failing or inadequate, then “inline”

replacement should be considered. This is a relatively expensive methods. We can upsize

the pipe. Existing pipe line is removed & a new pipe line is installed by pipe bursting. Pipe

removal is done by breaking/eating or by pipe displacement method.

Close fit pipe:- coiled deformed new pipe installed in the host pipe & expanded to its

original size & shape, after placement, to provide a close fit. (Example; Nu pipe, Am-liner,

U-liner, Swage lining, roll down pipe etc.)

Point source repairs :- when local defects like cracks, joint failure are found, point source

repairs are resorted to by remote controlled robotic structural repair, grouting, CIPP,link

seal shortcrete & epoxy coatings, spray-on-lining coats are also resorted to.

Sewer manhole rehabilitation: - sewer manhole requires rehabilitation for structural

defects, cracks, corroded concrete surface, etc. & to prevent surface water inflow & ground

water infiltration. Methods adopted are sealing epoxy, spray-on-lining, cast-in-place, cured

–in-place, & profile PVC, etc.

8


Pull Back:-back reaming is done only after the pilot bore is completed. When the sensor is

exposed at exit pit, the sensor is removed from the rod and Reamer attached to it,

depending on size of the product to be pulled.

Method of installation:-

Expanda process:-This process is specially designed for smaller diameter sewers (150 to

750 mm) and produces liner which closely fits to the existing host pipe.

Rib steel process: - This method is used for larger diameter sewers (>900mm).This

involves the production of new pipe slightly smaller than the existing host pipe. A winding

cage is lowered in to the manhole chamber.

Rotaloc Method:-The rotaloc winding machines is lowered to the base of the manhole

chamber through standard manhole openings. The PVC profile is fed in to the machine

from above ground spool.

CHAPTER NO.4

9


SAFETY MEASURE

Follow these guide lines before operating any jobsite equipment.

● Complete proper training and read operator’s manual before using equipment.

● Mark jobsite clearly and keep spectators away.

● Use equipment carefully. Stop operation and investigate anything that does not look or

feel right.

● Do not operate unit where flammable gas is present.

● Wear personal protective equipment.

Underground Hazards:

Striking underground hazards can cause explosion, electrocution, fire, and exposure to

hazardous materials.

Hazards include:

●Electric lines

●Natural gas lines.

●Fibre optic cables.

●Water lines.

●Sewer lines.

●Pipes carrying other chemicals, liquids, or gases

●Storage tanks

Electric Strike Description

When working near electric cables, remember the following:

●Electricity follows all paths to ground, not just path of least resistance.

●Pipes, hoses, and cables will conduct electricity back to all equipment.

●Low voltage current can injure or kill. Almost one-third of work related electrocution

result from contact with less than 440 volts.

Most electric strikes are not noticeable, but indication of a strike includes:

●Power outage

●Smoke

●Explosion

●Popping noises

●Arcing electricity

10


If any of these occur, or if strike alarm sound or flashes, assume an electric strike has

occurred.

If an Electric Lane is damaged

On Drilling Unit or Bonded Ground Mats:

1) DO NOT MOVE. Remain on drilling machine or mats.

2) Warn people nearby that an electric strike has occurred

3) Have someone contact electric company.

4) Reverse drilling direction and try to break contact. Do not touch drill pipe with hands

Or hand-held tools.

5) Press electric strike system status button.

*If alarm sounds again, stay where you are and wait for electric company to shut off

power.

*If alarm does not sound and there is no other indication of a strike, wait at least one full

minute before moving away from equipment. Utility might use automatic reclosers which

will restart current flow.

If a Gas line is damaged

● Immediately shut off engines(S) & remove any ignition sources.

● LEAVE AREA as quickly as possible.

● Warn others that a gas line has been cut and that they should leave area.

● Contact emergency personnel.

● Do not return to area until given permission by utility company.

If a fiber optic line is damaged

Do not look in to cut ends of fiber optic or unidentified cable.

CHAPTER NO.5

5.1 ADVANTAGES OF ADOPTING TRENCHLESS TECHNOLOGY

11


(a) Quality in construction

(b) Economy

(c) Speedy construction

(d) Skill up-gradation

(e) Accident free

(f) Reduces noise pollution

(g) Avoids traffic jam

(h) Saves resources

(i) Reduces damages of valuable surface

(j) It makes the use of the line (track) of the old pipe possible (pipe bursting).

(k) It reduces the impact on tree and flowers.

(l) It reduces the danger of improperly compacted excavation.

(m) It avoids annoyance of the residents.

(n) It saves under ground space.

(o) It reduces impact on the environment after cleaning the old pipe

5.2 DISADVANTAGES

High initial cost of equipment.

Skilled or trained person is required for handling the equipment.

In case of availability of huge labour force on cheaper rate going for this method

will be uneconomical especially in villages and small town etc.

Maintance cost and operation cost is more.

Spare parts of equipments are not available easily in market.

CHAPTER NO.6

12


APPLICATION/ USES

The following fields of application are crered by trenchless technology

Gas pipeline

Oil pipelines

Water pipelines

Sewer pipelines

Electric/power lines& cables

Data communication cables

Telecommunication cables

1) This method is very useful to lay utility lines below Airport Runway.

2) Trenchless technology is use where conventional method is impossible i.e. laid

utility lines below the 2m or more below the ground surface.

3) This method is very useful when the utility pipes lay under a Rail track or road

where conventional method is impossible.

4) This method is very useful when the utility pipes lay under a Riverbed or canal

where conventional method is impossible.

CHAPTER NO.7

13


COMPARATIVE STUDY

OPEN CUT METHOD TRENCHLESS TECHNOLOGY

1)Traffic hindrance: Traffic

obstruction,accidents,extra cost in providing

diversions and their maintenance etc.

1) Such disadvantages should be

eliminated by adopting this technology.

2)Environmental pollution: Dust & air

pollution by vehicle & machines, noise

pollution,pollution of ground & Surface

water

3)Commerce and industry: Loss of

sale,productivity,increase consumption

POL

4) Citizen & Society: Increased avoidable

cost in repair & rehabilitation the roads,

compensative for damages, advantage of

early availability of the utility & avoidance

of public hindrance etc.

5) Not imperative.

2) Eliminated.

3) Eliminated.

4) Eliminated.

5) Imperative.

CHAPTER NO.8

INDIAN USE OF TRENCHLESS TECHNOLOGY

14


1) City trunck main constructed with pipe jacking technique across national highways.

(NH4 & NH7)

2) Over 5km of microtunnelling was completed between March 2000 & July 2002 in the

suburbs of Mumbai, for Bombay Municipal Council (BMC). The initial works

comprising 800 mm & 1000 mm diameter pipelines were carried out by microtunnelling as

an expedient to overcome environmental disturbances that would be brought about by cut

& cover construction in the highly congested urban areas. Such was the success of the

project that the original range of pipe size was increased to include 1250mm pipes & the

scope of the works was extended within the life of the project.

3) MTNL & Calcutta telephones have already opted for utilization of no-dig technology for

laying cables.MTNL has awarded a contract for laying 185km of telephone cables using

this technology.

4) Now a day Reliance Company laid cable by using this method only.

5) Laying of 18 inches diameter feeder pipeline of HBJ (Hazira-Jagdishpur) across

Yamuna River near Indraprastha gas turbine power station in Delhi.

6) Oil & gas Commission laid to 28 m long &42 inches diameter pipeline across river Tapi

7) Gas Authority of India Ltd, using this technology, laid 18 inches diameter gas line

across river Gautami-Godavari35 m below lowest riverbed level. This crossing is 1719m

long and the longest in the world.

8) Jamnagar/Kandala-Loni LPG pipeline will originate at Jamnagar & terminate at

Loni .The pipeline runs through Gujarat (522Kms) Rajasthan (630 Km.), Haryana (75 Km.)

& Delhi (5 Km.).

CHAPTER NO.9

A CASE STUDY

The company motto is ‘Do not dig; we drill for your comfort’!

15


The project:

The work of laying twin HT cable from VIDHANA SOUDHA Bangalore to its new annex

building was entrusted to KEPL at a cost of Rs. 2.25 lakhs. Works was restricted to be

carried out only on Saturday & Sunday.

Details of work as follows:

Client : PWD- Vidhana Soudha

Contractors: Krita Engg. Pvt. Ltd. Bangalore

Site Location: Vidhana Soudha Road towards K.R. Circle

Strata : Murram & at certain points rock & boulders

Pipe length : 225mtrs (2*240sq mm cable plus one 14 core control cable)

After back reaming

Hole Dia. : 250mm

Cost : Rs.2.24 lakhs (@Rs 1000/-per meter)

Duration : 2 day (Saturday & Sunday) & 7 days for planning, survey &

mobilisation.

Before the work was taken in hand initial planning ,survey and mobilization took 7 days for

firm; actual instillation having taken 2 days only. Preliminary planning included following

activities:

* Survey

* Selection of route / layout

* GPR survey

* Selection of equipment

* Safety & security

* Traffic control

Survey:

a) Preliminary physical survey

b) GPR survey

c) Geotech consideration

CHAPTER NO.10

PHOTOGRAPHS

16


JEA High Volume Pipe Bursting Ohio River HDD Crossing

King County, Wash., Pipe Ram Assists

Pipe Burst During HDD Pullback

17


West Roxbury tunnel Tampa Bypass Canal Horizontal Pile

Driving

Temperature restrictions for HDPE

18

Temperature restrictions for HDPE

What is the biggest problem you


CONCLUSIONS

Within a short span of 5-6 years, the awareness of trenchless technology in India is quite

significant. With progressive adoption of trenchless technology in India, new equipment

and development of new materials will follow which will revolutionize the construction

industry and benefit the society. However, many planners, designers and engineers are not

yet accustomed to using them. Hence, there is a need for further technological refinement,

better information dissemination, and greater public awareness and understanding

regarding appropriate use of trenchless technology and its contribution to environmentally

sustainable urban development. It is hoped that seminars on this newer technology will be

encouraged which will promote greater awareness in adoption of this new technology for

the development and management of underground utilities.

19


BIBLIOGRAPHY:

Websites:

1. http://www.istt.com/net

2. http://ce.ecn.purdue.edu/cem/trench/piperamming.html

3. http://www.estt.org

4. http://www.nastt.org

Journals:

5. Journal of “Indian Society for Trenchless Technology”.

6. Trenchless Technology-Social cost by R.K.Sharma, NBCC Ltd.

7. Civil Engineering and Construction Review (May 2002).

8. Civil Engineering and Construction Review (April 2004).

9. ‘Underground utility infrastructure’ literature held at ‘Bangalore’

10. “Trenchless Technology- The India scene” by Dr.V.M.Sharma, Advance

Technology and Engineering services (AIMIL).

20

http://www.nastt.org/

http://www.estt.org/

http://ce.ecn.purdue.edu/cem/trench/piperamming.html

http://www.istt.com/net

Documents

Advances in Trenchless Technology