Seismic Performance of Flat Slab Buildings Considering P-Delta Effect

Abstract

Flat slab structures are becoming quite popular due to functional and architectural advantages. The flat slab structures are flexible when compared to framed structures as the slab is directly columns. Typically the seismic forces in such a structure are resisted by shear wall systems. Under design seismic conditions the lateral displacements are large and the columns deform along with the lateral load resisting system. Under such conditions the columns are required to remain stable under the vertical loads. Due to large lateral deformations, the secondary effects like P-delta become significant and hence need to be considered for correct estimation of design forces and deformations. Therefore, seismic behavior of a flat-slab structure needs special attention due to its flexible behavior and large lateral displacements and effects like P-delta assume significance. This paper examines the effect of P-delta on seismic behavior of flat slab buildings. A simple methodology has been proposed to include the effect in the analysis and examine the behavior through performance based approach.