Analysis Of Annular Raft Foundation using Finite Element Method

. A finite element analysis of an annular raft and a circular raft is undertaken in this work. Different ratios of inner radius to outer radius are chosen to examine the effect of geometrical characteristics of annular rafts. The ratio of radius of ring beam to outer radius of raft was also varied. Finite element method is adopted to determine critical moments and deflections in both annular and circular rafts. Comparison of these critical moments and deflections is made for both annular raft and circular raft,for selection of suitable type of raft foundation. Finite element analysis of both the rafts is carried out using ANSYS software.The results show that values of critical moments and deflections in annular raft are less in comparison with those values in circular raft. Different ratios of inner radius to outer radius and radius of ring beam to radius of raft effect critical moments and deflections.