Soil Structure Interaction Analysis on a RC Building with Raft foundation under Clayey Soil Condition

Abstract

During seismic activity, the response of structures is influenced by Soil Structure Interaction (SSI) which is the process where the response of soil particles to earthquake ground motion affects the motion of structure and the response of structure affects the motion of soil mass. In design offices the base of multi-storey buildings are taken as fixed and analyzed for earthquake response using provisions of IS 1893-2002 with the aid of response spectrum given for soft, medium and hard soils in foundation. But in reality, the type of soil present in and around the foundation structure also participates in the seismic response and the assumption of fixed base becomes conservative. Soil structure interaction usually carried out for soft, medium and hard soil. This study is mainly concentrated on in situ clayey soil conditions. The RC building considered to analyse SSI is an apartment of G+12Storey with an elevation of 40.15m and with the plan shape of 28.2mX16.1m proposed at Mambakkam, South Chennai, Tamil Nadu state, India. The study has used the finite element tools ETABS 9.7.4 for modeling and SAP2000 ver17 for SSI analysis.