Seismic Ground Response Analysis using Continuum Approach

Abstract

Conventionally, Ground Response Analysis (GRA) is carried out using a discrete approach in which a layered soil column is idealized as a multidegree of freedom lumped mass system. In this approach equivalent-linear or nonlinear soil model is used and the soil layers are assumed to be horizontal and infinitely extended. However, when these conditions are not met, the continuum approach to model soil column using finite elements is more realistic. Further, depending on the soil test data availability, the soil model may be chosen as linear, equivalent-linear or nonlinear. When the phenomenon of ground response analysis is numerically simulated, the boundary conditions of the numerical model and the input ground motions play an important role. The present study, aims to compare the results of 1D GRA using discrete and continuum approach. For this purpose ten different real Indian sites are considered and modeled in DEEPSOIL and ABAQUS. The results show a good agreement between the approaches adopted for 1D GRA. This study is a step forward to use continuum approach to carry out 1D and 2D ground response analysis.