Bandra Worli Sea Link-3rd Year

Salient Features: It is the first bridge in India across the open sea,

having length 5.86 km. & twin, 4-lane independent carriageway.

It’s Construction begin on 1.10. 2000 & opened to public on 24.3. 2010.

It’s cost was 1600 crore Rupees & built by the HCC (Hindustan Construction Company) .

The Sea Link reduces travel time between Bandra and Worli from 45–60 minutes to 7 minutes.

The Construction of the Sea Link Project is divided into five packages.

Package IV is from start of Toll Plaza in Bandra to Worli end was most challenging & comprising the following:

1. 800m long Precast Segmental Approach Bridge on Bandra side & 1400m long Precast Segmental Approach Bridge on Worli Side.

2.600m long Cable Stayed Bridge with 128m high Towers at Bandra .3. 350m long Cable Stayed Bridge on Worli Side with Pylons of 55m height.4. 200m long Precast Segmental Approach Bridge between Bandra & Worli Cable Stayed Bridge

Foundation: The project’s site geology consists of basalts, volcanic tuffs

and breccias with some intertrappean deposits. The strength of these rocks range from extremely weak to extremely strong.

The foundations for the BWSL project consist of 2000-mm diameter piles numbering 120 for the cable-stayed bridges and 1500-mm diameter piles numbering 484 for the approach bridges.

M60 grade of concrete was used & length of pile was 25m.

The working load on the approach piles ranges from 700 tons to 1500 tons whereas for the piles below the cable-stayed bridge working load is 2500 tons.

Cofferdam was constructed using circular steel caissons. These caissons were fabricated outside and towed to location using A-frame barge.

Osterberg load cell method was used for pile testing. the O-cell automatically separates the resistance

parameters i.e. Skin friction & End Bearing.

Pier Construction: Each bridge section, except at the cable-stayed portion, is

supported on piers typically spaced 50 metres (160 ft)apart. The cable-stayed bridge on the Bandra channel has a 50m-

250m-250m-50m span arrangement and on the Worlichannel it has a 50m-50m-150m-50m-50m span arrangement.

The deck of the carriageways: It consists of triple cell precast box girders supported on

piers & having the fish belly shape. Relocation of Launching Trusses using 1600MT capacity

Barge Mounted Crane – Asian Hercules.

All field segments are suspended from the Gantry, gluedand temporarily stressed together. Once the gluing operation is completed, span alignment to the Piers is followed. After alignment, the wet joints are cast .Once the wet jointsachieve the required strength, stressing of longitudinal PT is commenced .

Pylons: The largest pylons for the bridge consist of diamond shaped

128 metres (420 ft) high concrete tower at bandra side & 55m at worli side.

The tower legs are inclined in two directions & the section decreases gradually with height.

There are horizontal grooves at every 3m height which permitted inserts and vertical grooves for circular portion that requires special form liners as well as it requires attention for deshuttering.

Pylon was fabricated on site with M60 grade of concrete.

Schematic view of completed pylon

Cable-stayed spans:

Stay Cables used are ‘Parallel Wire Stay Cables’. Diameter of single wire was 7mm with a breaking limit of 6.28 Tones. Six different types of arrangement used were of 61, 73, 85, 91, 109 and 121 steel wires.

A centre tower, supports the superstructure by means offour planes of cable stay in a semi-harp arrangement. Cable spacing is 6.0 metres along the bridge deck.

The overall tower configuration is an inverted "Y" shapewith the inclined legs oriented along the axis of the bridge at bandra,whereas the overall tower configuration is "I" shape with the inclined legs at worli.

A total of 264 cable stays are used at Bandra channel withcable lengths varying from approximately 85 metres minimum to nearly 250 metres maximum.

A total of 160 cable stays are used at Worli channel withcable lengths varying from approximately 30 metres minimum to nearly 80 metres maximum.

Bridge management: For the Toll collection there are 3 ways:1.Automatic electronic payment system through On-board Units mounted on vehicles2.Semi-automatic cash-less electronic payment via smart card3.Manual toll collection for payment by cash

The control system comprises of emergency telephones,fibre-optic cables, CCTVs running the entire span of the BWSL.The bridge uses mobile explosive scanners for vehicles . Scans take less than 20 seconds for each vehicle.

Inflated buoys surround each pillar of the sea link to avoidany damage caused by explosions and collisions.

1.http://en.wikipedia.org/wiki/Western_Freeway_(Mumbai)( Accessed on 2.11.11)

2.http://mycoordinates.org/making-of-bandra-worli-sea-link/all/1/(Accessed on 2.11.11)

3.http://sea-link.blogspot.com/( Accessed on 2.11.11)

4.http://mumbaimatters.bombayaddict.com/2007/05/bandra-worli-sealink-some-photos.html( Accessed on 1.11.11)

5.http://www.dnaindia.com/mumbai/report_hi-tech-scanners-on-bandra-worli-sea-link-by-year-end_1415643( Accessed on 4.11.11)

6.http://www.hvfacprojectindia.com/resources/Fact%20Sheets/BWSL290705.pdf

7.http://www.livedarshan.com/livedarshan/en/pdf/HCC.pdf

8.http://www.citehr.com/attachments/53806-bandra-worli-sea-link-bandra_worli_sealink.pps

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