Non-linear Soil-Structure Interaction Analysis of Multi-storey Shear Wall Buildings with Site Specific Ground Response

Abstract

Influence of local geology and soil conditions play a major role in varying the intensity of ground shaking. In the present study, by utilizing the geotechnical data of a specific site, amplification of earthquake motion is found out by ground response analysis. Seismic structural response variation in multistory shear wall buildings with different shear wall locations is determined from nonlinear soil-structure interaction (SSI) analysis using the ground motion with the highest peak ground acceleration obtained from the site. Geotechnical data from twenty bore holes at the site with depth varying between 7–15 m below ground level are considered. This specific site is very near to the Arabian Sea coast with a lot of variation in the geotechnical profile. Symmetric plan multi-storey reinforced concrete shear wall buildings of aspect ratio (h/d) ranging from 1 to 4 resting on raft foundation with shear walls placed symmetrically along the exterior frames, core and all four corners of the exterior frames are considered. Further, the structural responses obtained from SSI analysis and conventional method of assuming rigidity at the base of a structure is compared. Results show the significance of positioning of shear wall in symmetric buildings which attracts the least earthquake forces, with the consideration of nonlinear behavior of the underlying soil medium.