Seismic Response of RC Frame Building Considering Soil Structure Interaction

Foundation is a load transferring part of structure to soil. Recent trends have made replacement of conventional practice of isolated and eccentric footing with Mat foundation. Necessity to choose Mat foundation over conventional isolated footing is when the bearing capacity of soil is considerably low. However, consideration of properties of soil in contact with the foundation has not been applied in detail practice which is also called soil structure interaction (SSI) will significantly affects the performance of structures. Our study has used Winkler’s method to model the foundation soil as spring Moreover, three different buildings of five, seven and nine story were modeled using finite element method to incorporate the soil structure interaction effects. performance parameter to measure the performance of the structures was done using Roof displacement. This research reports the change in natural time period, roof displacement and base shear due to consideration of SSI and concludes with the urge of consideration of SSI in structural analysis and design.