Research On Rc Frame Structures With Cast-in-place Slab

Reinforced concrete frame structure is a common structure form in the industrialand civil architecture. More attention has been paid to the seismic performance of RCframe structure. Frame structure design should meet the requirments of strong columnand weak beam. However, large numbers of data shows this goal was not achieved.Many complicated factors make the realization of strong column and weak beamyielding mechanim becomes diddicult. The effect of slab is one of the importantfactors. The effect of slab is a problem deserving of study.The works of this paper are summarized as follows.(1)A reinforced concrete frame structure is designed strictly according to Chinesecode. Three structures are establilshed by SAP2000software. They are framestructure with cast-in-place slab and slab reinforcement, frame structure withcast-in-place slab and frame structure without slab. The performance of the slab andreinforcement on frame structures under different earthquake level has been studied.(2)Slab thickness, column moment amplification factor and beam height can affectthe seismic performance of the framework.(3)Beam stiffness amplication factor is studied. Many of the frameword structureare establilshed by SAP2000and PKPM. The relationship between beam stiffnessamplification factor, slab thickness and beam height is studied.Based on the above research, the main conclusions are as follows.(1)Cast-in-place slab can increase the rigidity of the structure obviously.Also，it canreduce the ductility of the structure. In the different earthquake levels， floorreinforcement plays a different role.(2)Slab thickness, column moment amplification factor and beam heiget can affectthe structural stiffness and ductility effectively.(3)When the frame beam cross section is small and the slab is thick, beam stiffnessamplification factor will be greater than2.0. When the frame beam cross section islarger and the slab is thin, beam stiffness amplification factor will be less than1.3.The relationship between the beam stiffness amplification factor, slab thickness andbeam height is β=0.4694+4.836h/H.