Larsen & Toubro

Patna, Bihar

Service CategoryGeotechnical SectorHighway Engineering

To ease roadway access between north and south Bihar, a project has been taken up for construction of greenfield six-lane extra-dosed cable bridge over river Ganga near Kachchi Dargah. This involves the construction of a 22 km road alignment including a 9.76 km long extra-dosed bridge spanning the mighty Ganga After completion, this will be the country’s longest extra-dosed bridge.

The Government of Bihar acting through Bihar State Road Development Corporation Limited (BSRDCL) felt the urgent need of a Green Field Six-Lane Extra-doses Cable Bridge over Ganges connecting Kachchi Dargah in Dist. Patna on NH-30 to Bidupur and Vaishali district on NH-103.

The geotechnical investigation carried on extra-dosed main bridge and its approach connections (Via ducts, Embankments, ROBs, Major Bridges, and roads intersections/Junctions. The proposed location of the bridge was about 10 km downstream of existing Mahatma Gandhi Setu in Patna.

The overall objectives of the exploration were to study and evaluate the stratigraphy of the said project locations and to obtain Geotechnical parameters of the subsurface formations for design and construction of foundation for different structures. During the project twenty four boreholes were drilled up to a termination depth of 80.00 meter below the existing ground level of proposed major bridge. The entire fieldwork and laboratory test were conducted as per the standard specifications and instruction of supervision consultant.


Detailed Description of Actual Services Provided by the firm:

  • Detailed reconnaissance and Review of all available reports about the project.
  • Detailed Geotechnical Investigation for sub soil characteristics and strength.
  • Material investigation for embankment filling.
  • Laboratory testing of all recovered soil /rock samples.
  • Detailed geotechnical report preparation.

Main challenge was that we had to complete within 2 months because of Monsoon.