ONE-DIMENSIONAL SEISMIC ENERGY TRANSMISSION ALONG HETEROGENEOUS LAYERED SOIL

Abstract

In this present study an initiative has been taken to find out the modification in the seismic energy along distance its travel because of the soil heterogeneity. Soil heterogeneity is considered here in one dimensional analysis and analyses were performed using software DEEPSOIL. Both equivalent linear and nonlinear analyses were performed on homogenous and heterogeneous soil models: uniform loose sand, uniform soft clay and layered soil deposit of sandwiched clay layer between loose sandy soils. The performances of these soil models are compared here in terms of peak ground acceleration (PGA) value, and seismic energy migration in terms of Arias Intensity (AI) evolution along the depth inside the soil deposit. It is observed from the analysis that, less seismic energy and PGA is developed in the heterogeneous soil than that in homogeneous soil. This is because during earthquake more softening is taking place in the layered soil than that in uniform soil. Further in this paper the requirement of nonlinear analysis over the equivalent linear analysis is also presented.