Experimental Study On Seismic Behavior Of Regionally Confined Concrete Beams

The Regional Confined Concrete is a kind of confined concept proposed based on the ordinary confined concrete.The bearing capacity and ductility of Regional Confined Concrete is improved because longitudinal reinforcement and transverse stirrups was placed where the structural members need.As an important component of the building structure system,the seismic performance of reinforced concrete beam has play a important role in the seismic performance of the whole structure system.However,the ductility of the reinforced concrete structure is poor,which leads to the poor ductility of the reinforced concrete structure system,which hinders the development of the reinforced concrete structure system to a certain extent.In order to improve the bearing capacity and ductility of ordinary reinforced concrete beams,this paper presents a study on the regional confined concrete beams proposed.The Regional Confined Concrete beams is worked on that way: The square stirrups and longitudinal reinforcement are putted in the top and bottom part of reinforced concrete beam,forming different confined region in the cross section of concrete beam.The middle part of the beam is a weak confined part,and the upper and the lower parts are well confined part.When the external load is a cyclic load,the two well confined part and the weak confined part work together to make the Regional Confined Concrete beam to have higher bearing capacity and good seismic ductility.In order to study the seismic behavior of confined concrete beams,the experimental study and numerical simulation on the seismic behavior of two regional confined concrete beams and one normal confined concrete beam are carried out.The test results show that the ductility,bearing capacity and energy dissipation capacity of regional confined concrete beams was substantially increased when compared with ordinary reinforced concrete beams;The numerical results show that when the constitutive model for regional confined concrete is used in the numerical simulation of regional confined concrete,the experiment results agree with the the simulating results.At the same time,finite element method was used to analyze the RCC-1-1 beam,and drew the conclusion: because of the moderate increasing of stirrups,the bearing capacity and ductility of regional confined concrete beam(RCC-1-1)increased by about 15% when compared with RCC-1.