Influence of Slab System in Transfer of Lateral Loads to Reinforced Concrete Shear Wall

Abstract

: The function of the slab system in a building is mainly to carry the gravity load. There are different types of slab systems which will be selected based on gravity loading, length of loading span and requirement of the architecture. The structural engineers mainly concentrate on vertical loads while designing the slab system, even though slab systems provide a significant amount of lateral stiffness to the structures to resist the lateral loads. In some designs, the lateral stiffness of the slab system is taken into account while others do not. In this study, the influence of slab systems in the transfer of the lateral load to the lateral load resistance system is assessed. The target building type is a wall-frame system. To find out the influence of the slab system on the lateral stiffness of the wall-frame system, rectangular shape regular type buildings with different stories (5, 10 and 15 stories) are selected. Here, three different types of slab systems, such as slab and beam, flat slab and flat slab with drop panel, are selected. Next, the effect of structural response is investigated for the structures under seismic and wind forces, with and without lateral slab stiffness. In this study, the response (displacement, inter-storey drift, frequency and base shear distribution) obtained through modal response spectrum analysis, non-linear time history analysis and static wind analysis are used for comparison. From the responses, it is clear that the lateral stiffness of the slab system has a significant influence on the serviceability limit state design of a structure, but not to the ultimate limit state design. Considering the lateral stiffness of slab, the deformation of a structure is controlled by (5-15) %, (15-35) % and (30-55) % for SB, FS and FSDP, respectively, based on the structural height.