RESPONSE OF SATURATED SAND LAYERS DUE TO EARTHQUAKE EXCITATION

Abstract

This thesis examines the analysis of response of saturated sand layers due to earthquake excitation. The soil is modelled as an isotropic elasto-plastic strain hardening continuum. The numerical analysis is done using the bounding surface model for clayey soil. This model can simulate monotonic response of normal consolidated behaviour under ,cyclic loading conditions. This model is capable to simulate both the seismic induced excess pore pressure and hysteretic behaviour of saturated soils The bounding surface model is based on the frame work of critical state plasticity. The critical state plasticity and method of analysis for critical state soil models are also discussed. Special attention is given to the two phase media formulations and the finite element discretization of the governing field equations. The basic formulations governing the dynamic behaviour of saturated soils are derived on the lines of Blot's theory. An explicit-implicit time steping scheme is employed to solve the loosely coupled equations in the time domain. Numerical example of saturated sand layers subjected to earthqauke motion at the base demostrates the procedure