Solutions for Foundation Systems Subjected to Earthquake Conditions

Abstract

Soil–structure interaction plays an important role in dynamic behaviour of a foundation under combined static and seismic loadings. This paper describes a few case histories with field studies of deeply embedded bridge foundations to showcase the earthquake induced lateral effects using finite element framework. Rigorous dynamic approach with detailed numerical analysis for large diameter pile foundation and pseudo-static approach for rigid caisson foundation presented in this study demonstrated the functionality of foundation systems in seismic conditions. Efficacy of barrettes over piles as a cost-effective foundation solution in high-rise buildings has also been discussed by obtaining higher resistance under static condition. Finally, an analytical methodology considering three-dimensional passive wedge developed in front of the rigid caissons is presented for estimating the ultimate soil resistance under seismic condition. Closed-form expressions to determine seismic passive earth pressure coefficient and its distribution along caisson length for different embedment ratio have been explained here that can be adopted in practice to analyse foundation systems subjected to earthquake condition.