Soil Structure Interaction Study for High Rise Building

Abstract

In conventional analysis and design process of structures the effect of soil, which sup- ports the structure, is generally neglected. Behavior of structure also depends on soil strata. Actual behavior of structure can not be assessed without considering soil structure interaction (SSI) effect. SSI effect depends on many factors like contact pressure distribution below foot- ing, dynamic properties of soil etc. During earthquake, dynamic properties of soil are changed and that will change the response of structure also. For small struc- tures, these changes in response is not significant enough to affect design of members. Whereas for structures like dam, foundation of nuclear power plant, high rise build- ings, SSI effect will bring significant change in force, moment and stresses of the elements. Non consideration of SSI effect may cause under or over estimation of forces for any member. So, for such structures consideration of SSI effect in design is important. An attempt has been made to understand the behavior of high rise buildings (5 sto- ried and 12 storied) due to SSI effect. Two types of model (spring and elastic half space) has been taken for study of interaction effect. The behavior of building, forces, moments in members are changed after considering SSI. For three type of soils having different modulus of elasticity, analysis has been performed and estimation of actual forces, moments in member. Also the changes in the design of members are compared for fix base model and model with interaction effect.