Structural Analysis Model for Mat Foundations

Abstract

A simplified structural analysis model for mat foundations with grid floor beams as stiffeners is presented here. In the model, the Winkler type of subgrade reaction spring is assumed for the whole area under the mat foundation, and the yield-line theory of slab is used to lump the Winkler springs under slabs to the corresponding locations under the adjacent floor beams of the slabs. Therefore, each floor beam is now supported by springs with a segmentally linearly varied spring constant. The total analysis model for the mat foundation is then simplified to be a grid beam system on an elastic foundation with a segmentally linearly varied spring constant, and is subjected to loadings from the columns of the building structure. Some numerical comparisons with the results by a sophisticated finite-element model are made in order to demonstrate the effectiveness and efficiency of the presented analysis model.