SEISMIC ANALYSIS OF SHEAR WALLS CONSIDERING SOIL-STRUCTURE INTERACTION

The analysis of shear walls under ground motions is of great importance especially in multistory structures. The soil-structure interaction has a noticeable effect on the seismic response of shear walls because it affects the natural frequency of these walls. In this paper, a developed nonlinear finite element program is used to assess the seismic response of shear walls. The soil structure interaction problem is considered by introducing a modified model based on a combination between Duncan model and Mohr-Coulomb model and through using the coupled finite and infinite elements. The computer program is advantageous since it has many capabilities to calculate principle stresses, principle strains, deformations, crack angle and to draw the crack patterns at any time. A 45 m height shear wall with raft foundation on silty sand soil is analyzed under ALAKABA earthquake normalized to three different peak ground accelerations. Eight different masses are considered in the analysis to account for different values of dead loads carried by the wall depending on its location in the building. The time history of base shear and vertical stress at the wall base, wall deformation over its height and crack pattern are presented.