Seismic Response of Shear Wall Buildings with Rigid and Flexible Foundations

The significance of incorporating Soil Structure Interaction (SSI) effect in the analysis and design of RC framed structure is increasingly recognized but still has not penetrated to the large level owing to various complexities involved. It is a well-established fact that the SSI effect considerably influences the design of high-rise storey buildings subjected to lateral seismic loads. The shear walls are often provided in such structure to increase the lateral stability to resist seismic lateral loads. The paper presents a linear soil structure analysis of a G + 15 storey RC shear wall building frame resting on isolated footing and raft foundations and supported by deformable soil. The modeling and analysis is carried out using ETABS 2015 software under gravity loads and seismic loads. The interaction work analysis is carried out with and without shear wall to study the effect of inclusion of shear wall on the forces in the footing due to settlement of soil mass. Both the frame and soil mass are considered to behave in a linear elastic manner. It is observed that the SSI effect significantly alters the time period, base shear, stiffness, storey drift and storey forces of the building due to soil settlement. The non-interaction analysis of space frame shear wall suggests that the presence of shear wall significantly reduces time period and displacement of the building but the interaction effect causes restoration of time period and displacement to a great extent.