This document provides information about the Bangalore Metro Rail project in India. It discusses the history of mass rapid transit proposals for Bangalore going back to 1982. It describes some of the early feasibility studies and proposals for metro and commuter rail systems. It outlines the formation of the Bangalore Mass Rapid Transit Limited in 1994 to implement a mass transit system. The document then discusses the Delhi Metro Rail Corporation's 2003 proposal for the Phase I of the Bangalore Metro project, which was eventually approved in 2005. It provides details about various aspects of the metro system's construction, including piling, elevated viaduct construction using precast segments, and underground tunneling using tunnel boring machines. It also shares experiences from site visits to different construction

1. LARSEN & TOUBRO LIMITED
ECC DIVISION
Submitted by:
DIVYASHREE
Under the guidance of
C.T.VENKATAPPA (Project Manager)
K.ARUL ANANDHAN (Deputy Project Manager)
RAJENDER (Engineer)
SEETHARAM (Engineer)
NAGALINGAM (Engineer)

2. Bangalore (also Bengaluru) in the south west of India is the country's fastest-growing
metropolitan area. It seems to set to confirm a place as the third-largest city with a population of
well over five million and with more in surrounding satellite communities. The state capital of
Karnataka, Bangalore is a leading research centre with a concentration of the international
information technology industry.
An important location for Indian Railways, Bangalore's urban transport has been made up of
taxis, buses and lightweight powered rickshaws. Coupled with the need to sustain the city's
growth, the social and economic transformation has focused official attention on developing
rapid high-volume rail-based public transport.
Several MRTS proposals for Bangalore have been in the pipeline for nearly 24 years. In 1982, a
study suggested that the MRTS should have a route length of 12.20 km. and pegged the cost at
Rs. 239.15 crores.
In 1983, the Metropolitan Transit Project, an organization of Indian Railways, prepared a
feasibility report for provision of suburban rail services on existing lines, a circular railway of
57.9 km. metro system on two corridors, in Phase-I 12.9 km. from Rajajinagar to Jayanagar and
in Phase - II 11.2 km. from Hudson Circle to Krishnarajapuram. In 1988, a World Bank aided
study was carried out by RITES and the study recommended a Commuter Rail System along
with improvement of road transport system.
Later, in 1994, the Bangalore Mass Rapid Transit Limited (BMRTL) was incorporated by the
State Government to implement the mass rapid transit system. BMRTL in turn asked the IL&FS
to carry out a feasibility study for LRT System on Public-Private Partnership. However, though
the partner was selected, the project did not take off. Later, Delhi Metro Rail Corporation
(DMRC) in partnership with RITES prepared a Detailed Project Report (DPR) for Bangalore
Metro Rail, Phase I in 2003 at the instance of the Government. It proposed two double line
corridors: East-West (EW) and North-South (NS) with a total length of 33 km.
The Bangalore Metro Rail finally took shape with the Karnataka Government clearing the
project in March, 2005 and the Union Government giving its approval in April, 2006.

3. With traffic decongestion being the key, the primary aim of the Bangalore Metro is to encourage
commuters to leave their vehicles in their garages and use public transport. Positioned as a
complementary, rather than competitive mode of transport, the Bangalore Metro will work in
tandem with other transport systems like buses and mono rails.
The city bus corridors will not run parallel to Bangalore Metro corridors, instead buses will act
as feeders. The mono rail network planned for the city will not overlap with that of the metro, but
will connect at major junctions as feeders.
On certain high density corridors, three wheelers will be regulated. Feeder bus services will be
provided to all the metro stations. Bus bays and parking facilities for private vehicles will be
available at all major stations. State-of-the-art satellite bus-cum-metro terminals are being
planned in the city outskirts, to control the entry of inter-city buses.
The Bangalore Metro will be integrated with Railways and other modes of transport at
Baiyappanahalli Railway Station in the East, Yeshwantpur Railway Station in the North and
Bangalore City Railway Station and Kempegowda Bus Stand in the Central parts of the city.

4. PROPOSALS FOR METRO
Several MRTS proposals for Bangalore have been in the pipeline for nearly 24 years. In 1982, a
study suggested that the MRTS should have a route length of 12.20 km. and pegged the cost at
Rs. 239.15 crores.
In 1983, the Metropolitan Transit Project, an organization of Indian Railways, prepared a
feasibility report for provision of suburban rail services on existing lines, a circular railway of
57.9 km. metro system on two corridors, in Phase-I 12.9 km. from Rajajinagar to Jayanagar and
in Phase - II 11.2 km. from Hudson Circle to Krishnarajapuram. In 1988, a World Bank aided
study was carried out by RITES and the study recommended a Commuter Rail System along
with improvement of road transport system.
Later, in 1994, the Bangalore Mass Rapid Transit Limited (BMRCL) was incorporated by the
State Government to implement the mass rapid transit system. BMRCL in turn asked the IL&FS
to carry out a feasibility study for LRT System on Public-Private Partnership. However, though
the partner was selected, the project did not take off. Later, Delhi Metro Rail Corporation
(DMRC) in partnership with RITES prepared a Detailed Project Report (DPR) for Bangalore
Metro Rail, Phase I in 2003 at the instance of the Government. It proposed two double line
corridors: East-West (EW) and North-South (NS) with a total length of 33 km.
The Bangalore Metro Rail finally took shape with the Karnataka Government clearing the
project in March, 2005 and the Union Government giving its approval in April, 2006.
Comfortable Travel.. Priceless!
The Bangalore Metro comes with a package deal. Comfortable, quick, safer and economical, its
energy requirement per passenger km. is only one-fifth of that of road based systems.
Commuters can breathe easy; there will be no air pollution as the system runs on electric power.
The economic rate of return is 22.3%
The Bangalore Metro construction work on the first elevated section (Reach-1) from
Baiyappanahalli to Cricket Stadium (7 km.) is expected to be commissioned by within the first
half year 2011.
BMRCL is seeking to minimize public inconvenience during the construction period.
Prefabricated viaduct segments will be launched during night time, to avoid disruption of traffic.
The frequency of the Metro trains will be every four minutes initially. This would increase to
three minutes by 2021. The travel time from end to end on the east-west corridor will be 33
minutes, and on the north-south corridor 44 minutes. The system is designed for a maximum
train speed of 80 kmph.

5. SITE VISIT & INVESTIGATION
Pile Construction:
In metro construction the elevated structure is supported with required foundation.
Friction piling method is the method used in Bangalore Metro. Before construction of
pile ground movement testing and soil testing was conducted by geotech-engineer.
A Pier is supported over six piles, initially tests are carried out to find the depth of hard
rock by using a chisel weighing one ton and dropping it with 1000 blows, depending on
the settlement it is decided whether it is hard rock or soft rock, if settlement is less than
200 mm then it is said to hard rock, if it is more than 200 mm then it is said to be soft
rock.
In any case, if hard rock is not found then pile is driven to a depth of 32 m.
For hard rock, pile is inserted 1.2 m inside and for soft rock 3 m inside.
Steps carried out for construction of a Pile:
1. Requisition for inspection
2. Detailed survey
3. Cage reinforcement
4. Cage lower
5. Flush(Bentonite)
6. Pour card
7. Trimmie chart
8. Concrete DC
9. Slump report
10. Pile cap.
Over the pile cap, pier is constructed; a crash barrier is constructed around the pier
bottom to avoid accidental damage to the pier.

6. ELEVATED CONSTRUCTION
For the elevated sections, pre-cast segmental construction for super structure for the viaduct was
used. For stations also the superstructure is generally of pre-cast members. The pre-cast
construction reduces the construction period due to concurrent working for substructure and
superstructure, minimizes inconvenience to the public utilizing the road as the superstructure
launching is carried out through launching girder requiring narrow width of the road, and ensures
good as the pre-cast elements are cast on production line in a construction depot. For a segmental
pre-cast element (of generally 3.0 m length), transportation from construction depot to site is also
easy and economical. The method is also environment friendly as no concreting work is carried
at site for the superstructure.
For viaducts segmental pre-cast construction requires a casting yard. The construction depot will
have facilities for casting beds, curing and stacking areas, batching plant with storage facilities
for aggregates and cement, site testing laboratories, reinforcement steel yard, fabrication yard,
etc. An area of about 2.5 Hect. to 3 Hect is required for each construction depot (one per
contract). For casting of segments both long line and short line method can be adopted. However
the long line method is more suitable for spans curved in plan while short line method is good for
straight spans. A high degree of accuracy is required for setting out the curves on long line
method for which pre calculation of offsets is necessary. Match casting of segments is required
in either method. The cast segments are cured on the bed as well as in stacking yard. Ends of the
segments are to be made rough through sand blasting so that gluing of segments can be effective.
The cast segment will be transported on trailers and launched in position through launching
girders. Launching girder is specially designed for launching of segments. Initially, the launching
girder is erected on pier head at one end of the work. The segments are lifted in sequence and dry
matched while hanging from the launching girder. After dry matching, the segments are glued
with epoxy and pre-stressed from one end. The girder is lowered on the temporary / permanent
bearings after pre-stressing. The launching girder then moves over the launched span to next
span and the sequences continue.
Sub-structure for the elevated section consists of open foundations in rock area and pile
foundations where soil is encountered or rock is more than 5 to 6 m below the ground level. Four
piles of 1200 mm diameter were provided.. A pile cap of thickness of about 2 m was cast over
the piles. The pile cap /open foundation top was kept about 500 mm below the road level so as to
provide necessary drainage from the viaduct and leave space for crossing of utilities if necessary.
Circular pier of about 1600 mm diameter was cast in single lift including pier cap to give good
finish without any joint in the concrete. For protection of the pier from collision from moving
vehicles on the road, a concrete guard is also provided around the pier up to a height of 1 m.

7. UNDERGROUND CONSTRUCTION
The underground work of Phase I commenced in May 2011. Each corridor consists of two
tunnels which are the first underground tunnels built for trains in South India. The tunnels, dug
using tunnel boring machines (TBM), are located approximately 60 feet below ground level,
have a diameter of 5.5metres and are 5metres apart. A total of 6 TBMs were used for work in the
underground section of phase I. They were nicknamed Helen (TBM 1), Margarita (TBM
2), Kaveri (TBM 3), Krishna and Godaveri.
Detailed geo-technical investigations revealed that in the areas where underground tunneling had
been proposed, hard rock was not expected to be met except on the stretch from km 8.751 to km
9.018 on the Post Office Road where hard rock is approximately 8 m below the ground level.
The ground water table for underground construction was estimated to be between 3 to 5 m.
Earth pressure balanced mechanized shields with an external diameter of 5.95 m. and a finished
internal diameter of 5.2 m. were employed for boring tunnels through this soil strata. The tunnels
have a minimum cover of 6 m ordinarily and in exceptional areas it can be reduced to even 3.52
m. with special precautions. Cutter wheels of these shields are capable of cutting through stiff
hard soil and not through rock. The shield operations will not cause any ground settlement of
more than 8 to 10 mm provided the required pressure in front of the shield is maintained. DMRC
took expert opinions from internationally reputed tunnel shield manufacturers like Herrenknecht
of Germany and they opined that there would be no difficulty in designing and supplying the
required tunnel shields for this project together with the backup ancillary equipment’s needed for
excavating the tunnels. These manufacturers generally take about nine months time for design
and supply of a tunnel shield. The Herrenknecht shields used in Delhi Metro construction
performed well in soft soil giving a maximum rate of 25 m of finished tunnel progress a day and
an average rate of 9 to 10 m a day. The tunnel shields were assembled in the station shaft of City
Railway Station and the drive was continuous right up to the end of Cubbon Park. The shields
went through the station excavations for which it was necessary to ensure that the station
excavations were complete (though not the station box) before the shields reach the respective
locations. After the up line tunnel is completed the shield was dismantled and brought back to
the starting shaft and the down tunnel has to be driven. In regard to the North South line the
starting shaft was proposed just after the ramp near the Swastik station and the two tunnels
should be driven from this starting shaft. The exit shaft for dismantling and taking out the shields
was proposed at the City Market Station itself.

8. EXPERIENCE AND RESPONSIBILITIES AT CONSTRUCTION SITE
As a part of In-Plant Trainer following are the responsibilities, like visiting several sites both
underground and elevated construction sites, site office, review site drawings, gain knowledge in
conducting site tests, methods, management level skills, documentation, estimates and schedule
of project.
VIDHANA SOUDHA TUNNELING UNDERGROUND STATION
Basics of tunneling construction
Tunnel excavation using tunnel boring machine
Study of underground shoring and bulkheads for vertical wall
Dewatering ground water
Types of lateral earth pressure forces acting
Soil sample testing
Learning safety instruction onsite
MAHALAKSHMI LAYOUT ELEVATED STATION
Basics about metro construction and it is purpose
Detail study of construction methods
Safety Measures in the site
Erection of girder members
Types of girders and how they are placed
Study of elastomeric bearing
Detail study of pile and the tests conducted onsite and laboratories
Different levels of metro station
Off road structures
Bar Bending schedule
Different grades of concrete used in metro work for different structures
Use of coupler system instead of lapping
YESHVANTHPUR ELEVATED STATION
Detail study about architectural and structural drawings
Information about the transition piers
Process of piling carried out for off road structures
Integrity test conducted on pile
Retaining wall constructed in order to retain ground level earth pressure
Information about corbel and foundation bolts
Erection of steel structure at platform level
Concrete blocks and modular blocks

9. SOAP FACTORY ELEVATED STATION
Study of Simply supported piers
Information about crash barriers
Alignment variation in last 3 piers towards yeshvanthpur
Workability and pouring of concrete for last x-girder
Level calculation for different staircases
Concrete quantity calculation for different staircases and slabs
Guiding laborer for staging work
Concreting of footings, columns, landing beams etc
Land issue problems for offshore structures
Heavy traffic congestion during day time
PRECASTING YARD (PEENYA)
Process of pre casting of different types of girders
Method of pre-tensioning
Method of post-tensioning
Molding and de-molding of shutters
Alignment of shutters
Fixing vibrators to formwork
Process of concreting
Normal curing (21 days)
Steam curing (8 hours)
SITE OFFICES
Detail study of architectural and structural drawings
Process of Change orders, pay application review, clarifications, proposals,
specification and request for information (RFI).
Familiar with Submittals, quantities/procurement, and general scheduling at the
job site.
Documenting daily activities, scheduling future work, & reporting onsite work
issues to site office.

10. PHOTO GALLERY