Effects of flexural rigidity and soil modulus on the linear static analysis of raft foundations

Abstract EN

It is a common practice to assume infinite rigidity when analyzing and designing mat foundations, using the conventional “rigid” method, a case in which the effects of the mat flexural rigidity and the modulus of subgrade reaction of the supporting soil are ignored.

The intent of this research is to investigate the effect of the flexural rigidity, modulus of subgrade reaction and the corresponding variations of the pressure of the soil under the foundation in the linear static analysis results (bending moment, shear forces, and deflection) in a typical raft.

The soil is considered to be homogeneous elastic materials and the linear finite element analysis is carried out by using the rectangular four-node thick plate element, in which the shear deformation is taken into account.

It was concluded that the flexural rigidity considerably affects the analysis more than the soil modulus.