STUDY OF EFFECT OF SSI ON SEISMIC RESPONSE OF AN IRREGULAR RC STRUCTURE ON SLOPING GROUND AND ITS RESPONSE CONTROL BY USING BRACINGS

Omkar Avinash Ratnaparkhe; S.N. Deshmukh

Abstract

Structures located on sloping terrain surface are more susceptible to earthquake because of uneven plan and elevation irregularities. Lately, high-rise buildings have been design with various plan and elevation irregularities to elevate their visual aesthetics. In the most of cases, the structural analysis under an earthquake load has been done without considering the effect of soil-structure interaction (SSI), thereby it may not reflect the actual seismic response of the structures. In the present study an attempt is made to examine the effects of flexible base i.e. considering SSI and fixed base i.e. without SSI on the seismic response of an irregular structure on sloping ground and to regulate its seismic response by using bracings. A RC framed of G+14 structures on sloping ground by considering medium soil are considered for the study having regular rectangular shape and other having irregular T-shape in plan. Response spectrum analysis (RSA) including SSI has been carried out in ETABS software to obtain the response of building. It is observed that inclusion of SSI into the analysis shows the effect on response of structures and its effect on parameters like modal mass participation, storey displacement, max storey drift, torsional displacement, modal time periods and base shear. It is also seen that by placing the bracing at suitable location in a rectangular as well as t- shape building with inclusion of SSI, the seismic response of structure is reduces effectively.

Abstract

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