REHABILITATION WORK OF HIGH LEVEL PRESTRESSED CONCRETE BRIDGE ACROSS NARMAOA RIVER AT INDIRA SAGAR PROJECT

摘要

Indira Sagar Project (ISP) is one of the major project is being constructed in Narmada basin with largest storage capacity in the country. The project is located near Punasa village in Khandwa District of Madhya Pradesh with Irrigation potential of 1.69 lakh ha. Generating capacity of 1000 MW with drinking water facility. Initially a low level submersible bridge was constructed. But in the monsoon period it remained submerged and as there was no high level bridge to connect the both banks of river Narmada, hence a high level Bridge was constructed. It is to mention here that design discharge of the river is 84,000 cumecs and there was lot of discharge during the lean season also. The maximum height of pier is 41m over the riverbed and the longest continuous span is 47-60-47 m with other spans of 44-44m two span continuous type. The troubles of distress, shrinkage, creep etc. were observed resulting in sagging of bridge spans due to loss of pre-stress with cracks in box girders, cracks in concrete roller bearing and malfunctioning of expansion joints etc. Hence to strengthen the HL Bridge for its useful longer life, the rehabilitation work of bridge was planned and successfully executed in August 2004.