SEISMIC ANALYSIS OF BRIDGE ABUTMENT AND WELL FOUNDATION IN C-q) SOIL

Abstract

Bridge abutments are massive structures that act as end supports to the super structure of a bridge and retain earth, on the back side, which serves as an approach to the bridge. The stability analysis of a bridge abutment is complicated because of its dependence on a number of factors. The soil on which an abutment is constructed not only determines the abutment's bearing capacity but also the pressure exerted on its walls, which can pose a threat to its stability under critical conditions. Simultaneously other parameters like water table, cohesion, load acting on the abutment, surcharge, seismic accelerations etc play significant roles in the stability /instability of the abutment. In this study, a river bridge abutment retaining c.-c1 backfill has been considered. Exhaustive literature is available on abutments founded on cohesionless soil and hence the aim of this study was to understand how cohesion and water pressure affects the stability of an abutment under seismic accelerations and also to study the influence of these parameters on abutment width. In a similar manner, stability analysis of a well foundation has been carried out as well taking into consideration c-c soil. Derivations have been carried out for both elastic energy and ultimate resistance approach