Design of circular footings considering soil-structure interaction.

The effect of Soil-Structure Interaction (SSI) on the structural response of circular footing is studied. Linear behavior of soil is considered in the study. Initially, a building frame is analyzed using STAAD Pro. and a circular footing for the central column is designed manually. The circular footing is modeled as a 2-D (or) area element and FEM analysis is carried out using ANSYSl. Four-noded isoparametric element with six DOF at each node, is adopted for discretizing the circular footing model. The greater bending moment at the face of the column was observed in comparison to the conventional design. The SSI is induced by assigning modulus of subgrade of soil as elastic foundation stiffness which resembles Winkler's foundation model. Due to the effect of SSI, it is observed that the maximum bending moment of the circular footing at the face of the column is decreased and hence resulting in the requirement of the lesser area of main reinforcement. Therefore, SSI leads to the economical design of circular footing. Further reduction in bending moment and main reinforcement area is noticed for the square footing of equivalent area. [ABSTRACT FROM AUTHOR]