Micropile foundation for bridge over river shyok in Ladakh region – first bridge of its kind in the countary -A case study

This particular paper deals with construction of 10x140 ft TBR Extra-wide class-70R Bailey Bridge on micropile foundation in Ladakh region. It is the first bridge of this kind in the country which has been constructed on micropile across a riverine bed that too at an altitude of 14,500 ft across river Shyok in Ladakh region on road Darbuk – Shyok -Daulat Beg Oldi (D-S-DBO) which cuts across the treacherous route along the Shyok River at km 150.400. The location being very critical and important, required to be bridged urgently to ensure smooth flow of traffic. Upon analyzing the technical viability, ease and speed of construction, it was decided to construct 10 x 140 feet TDR CL 70R EWBB over micropile foundation which is a small diameter pile, generally less than 300 mm, drilled and grouted pile that is typically reinforced.

The design for the substructure using micro pile foundation was arrived at after carrying out a detailed subsurface Investigation and carrying out vertical and horizontal load test. The design of micro pile foundation comprises of 21 m X 273 mm diameter perforated casing with designed reinforcement.