Influence Of Reinforcement Type On Seismic Behavior Of Concrete Composite Slab With Precast Ribbed Bottom Panels

A new RC composite slab-concrete composite slab with precast ribbed bottom panels was studied in this paper. The major research is that the influence on seismic performance of precast ribbed bottom panels with different reinforcement in cast-in-situ concreteIn order to solve the research problems, a standard reinforcement specimen was designed with transverse reinforcements and bending reinforcements according to the requirements of standard drawings. Six other contrast specimens were designed on the basis of the standard reinforcement specimen with no transverse reinforcements, no bending reinforcements, double tranverse reinforcements, double bending reinforcements, change the direction of loading. The in-plane low cyclic reversed loading test has been carried out on the above seven specimens with different types of reinforcement. The failure patten, bearing capacity, displacement, ductility and stiffness of composite slabs with precast ribbed bottom panels were compared and analyzed based on the test. The influence of different types of reinforcement on seismic performance of composite slabs with precast ribbed bottom panels was studied too. The researches show that:the bottom plastic zone height and ultimate displacement of specimen were increased with the amount of transverse reinforcements or bending reinforcements. The transverse reinforcements and the bending reinforcements had a big impact on bearing capacity of specimen. The ductility of specimen increased with the amount of bending reinforcements but the ductility increased first and then decreased with the amount of transverse reinforcements. Both transverse reinforcements and bending reinforcements had a small impact on stiffness of specimen. Based on the expermental studies results, the composite slabs with perecast ribbed bottom panels must be designed with transverse reinforcement and bending reinforcement at the same time in actual structures. It is better to increase the amount of transverse reinforcement and bending reinforcement in seismic reigon, which can improve the seismic perforcemance of the composite slab.The finite element analysis on the above seven specimens was carried out by finite element software ABAQUS. The finite element calculation results had good agreement with the test results, such as failure patten, crack load, peak load and reinforcement strain. Based on the finite element analysis results, a further rsearch is taken on stress state of pre-stress wires and longitudinal bars in boundary beams. The stress state of reinforced skeleton frame of specimen was given based on the above finite element analysis, which can provide basis for theoretical research.The calculation method of crack load, yied load, peak load and ultimate load for specimen were put forword on the basis of test and finite element analysis results. The calculation results had a good agreement with the test results. And then the restoring force model of specimen was bulit based on the load calculation method. The load-displacement curves calculated by the restoring force model had a good agreement with the load-displacement curves measured in experiment.