Analysis Of Seismic Behavior And Bearing Capacity Of BFRP-Plate-Reinforced Composite Double Coupling Beam

BFRP-plate-reinforced composite double coupling beam is a new type of coupling beam,which is formed by opening a horizontal through joint along the span direction of the coupling beam on the coupling beam.The plate is built in the double coupling beam and the BFRP cloth is wrapped on the concrete surface.The coupling beam has high bearing capacity,strong energy dissipation capacity,good ductility and strong holding capacity,however,at present,there are few and incomplete researches on this type of composite coupling beam at home and abroad.Therefore,the seismic behavior test and theoretical analysis of this type of coupling beam are carried out in this paper.The main work and research results are as follows:(1)In this experiment,four specimens of the coupling beams were made and completed,the failure modes and characteristics of the specimens of the ordinary reinforced concrete coupling beam(RC),the ordinary reinforced concrete double coupling beam(RCD),the plate-reinforced composite double coupling beam(PRCD)and the BFRP-plate-reinforced composite double coupling beam(PRCD-B)were analyzed.The seismic behavior indexes such as hysteretic curve,skeleton curve,bearing capacity,ductility,stiffness degradation,strength attenuation and energy dissipation capacity are obtained.The distribution of strain of BFRP with displacement and time was analyzed by using the new DIC testing technology.The test results show that the ductility,energy dissipation and bearing capacity of the double coupling beam with steel plate and BFRP were significantly improved.(2)The finite element software ABAQUS was used to simulate and analyze four test specimens,the distribution laws of concrete stress,reinforcement stress,steel plate stress and BFRP distribution stress of each specimen were analyzed,and the distribution laws of axial force,bending moment and shear force of steel plate were analyzed.The parameters were analyzed based on the BFRP-plate-reinforced composite double coupling beam,this paper mainly analyzes the influence of the number of layers of BFRP,span-to-depth ratio,steel plate ratio,stirrup reinforcement ratio,longitudinal reinforcement ratio,the spacing of joint between coupling beams and concrete compressive strength on its seismic behavior,mainly from the shear bearing capacity analysis.The results show that the number of layers of BFRP,span-to-depth ratio,steel plate ratio,longitudinal reinforcement ratio and concrete compressive strength have significant influence on the seismic behavior of the specimens.(3)Based on the equivalent model of reinforced concrete double coupling beam,the bearing capacity model of plate-reinforced composite coupling beam and the bearing capacity calculation model of FRP reinforced concrete,the theoretical calculation method of BFRP-plate-reinforced composite double coupling beam was put forward,through verification of test data and simulation data,the results are consistent,this method is reasonable to calculate the bearing capacity of the BFRP-plate-reinforced composite double coupling beam.