Seismic analysis of piled raft foundations of tall chimneys considering the effect of SSI

Abstract

A direct method of Soil-Structure Interaction (SSI) analysis of 300m and 400m tall slender Reinforced Concrete (RC) chimneys with piled raft foundation subjected to Elcentro (1940) ground motion is carried out in the present study. The parametric studies have been conducted by taking different geometrical properties of raft of piled raft foundation and different material properties of soil stratum to understand the significance of SSI. Different responses in chimney, raft and pile are evaluated. The bending moments in raft and base moment of chimney with and without considering the SSI effect are compared. The maximum radial moment in raft of the chimney-foundation system resting on loose sand is more than that obtained from the conventional analysis whereas a reduction in tangential moment is seen when the piled raft foundation with rigid raft interacts with loose sand. � 2015 Taylor & Francis Group, London.