Soil-Solid Raft Interaction Analysis Subjected To Seismic Forces

Abstract

The response of a raft foundation to seismic loading, and examines the changes in soil consideration and importance factor suggested in the latest seismic codes, IS 1893-2002 and IS 1893-2016. The two methods of analysis suggested by IS 2950-1981 code, rigid and flexible approaches for vertical and evenly distributed loads are examined. Literature review reveals that soil-structure interaction and finite element analysis are used in analysis and design of raft foundation. A case study is conducted to compare the manual calculations and rigid method with finite element methods and soft computing techniques. The results of the study conclude that the deflection, bending moment and soil pressure per meter width are effectively expressed in terms of relative stiffness factor, and that the magnitude of maximum bending moment increases with increase in the relative stiffness. The established variation patterns of contact pressures may not be applicable for raft under dynamic loading condition.