Study On Seismic Behavior Of Steel-concrete Composite Frames Considering Interface Slip

Steel-concrete composite beam structure has higher strength,stiffness and ductility than ordinary reinforced concrete structure,and can better resist earthquake action.There is inevitable interface slip between steel beam and concrete.The existence of relative slip will increase the deformation of composite beam,decrease the stiffness and decrease the bending capacity of section.In this paper,the seismic behavior of steel-concrete composite beam structures is analyzed,and the flexural moment-curvature restoring force model of composite beam with slippage effect and the effect of multiple factors on elastic seismic response of composite frame are studied.1、A method for calculating the key parameters of the three-fold skeleton curve of the section bending moment-curvature considering the interface slip of composite beams is proposed,and a three-fold skeleton curve model of the section bending moment-curvature of composite beams is proposed,which is convenient for practical application.The moment-curvature hysteretic model of section of steel-concrete composite beams is also proposed.2、The nonlinear finite element analysis of composite beams,using the large finite element software Ansys,to create the finite element model of composite beams,and adopt the suitable material constitutive relation and finite element analysis of a load simulation of the cycle,and will get the skeleton curves and the hysteresis of the finite element model and the calculation results are compared,verified the validity of the calculation formula,and analyzed the influence of shear connection degree of composite beams.3、Based on the existing theoretical basis is deduced considering the slip effect and the effects of floor space combination and the composite frame beam element stiffness matrix of semi-rigid nodes,through the analysis of the Matlab program for dynamic analysis of composite frame,the slip effect,floor space combination effect and semi-rigid connection of combination frame natural frequency of vibration and the influence of elastic seismic response.4、By changing the shear joint degree of composite frame and the amplification coefficient of steel beam,the influence of the interface slip between steel beam and concrete wing slab and the spatial combination effect of floor slab on the elastic earthquake of composite frame was studied,and the parameters of these factors were analyzed..