Experimental Research On Seismic Behaviors Of Steel Reinforced Concrete Columns Of Asymmetric Configuration Steel

Steel reinforced concrete structure is to point the main configuration steel in concrete (rolling or welding forming), and equipped with a certain force and construction of reinforced steel, which is one of the main form of the steel and concrete composite structure, it has better seismic performance and durability, according to the different configuration steel form,reinforced concrete structure can be divided into steel reinforced concrete structure of symmetry configuration steel and steel reinforced concrete structure of asymmetric configuration steel, and this paper studies the the seismic performance of asymmetric steel SRC column, In this experiment, the cross section shape have T and L two kinds, shear span is2.5, match steel rate is5.19%, match stirrup ratio is1.346%,1.256%,1.675%, axial compression ratio is0.4and0.6,the main research contents and the results of analysis are summed up as follows:(1) This paper researched the seismic performance of T-shaped SRC column of asymmetric configuration steel at different axial compression ratio and the stirrup ratio:the hysteresis curves of steel reinforced concrete column of asymmetric configuration steel are full, skeleton curves’s decline period are gentle, it has better ductility and energy dissipation capacity, the steel reinforced concrete column of asymmetric configuration steel has good seismic performance. through analysis the axial compression ratio and the stirrup ratio to the influence of the component ductility, we can draw the conclusion, the volume stirrup ratio and axial compression ratio to steel have great influence on the ductility, the stirrup ratio is the bigger, and the ductility and energy dissipation capacity are better, the axial compression ratio is bigger, the shear carrying capacity is relatively large, but the deformation is relatively small, the ductility is poor.The energy dissipation capacity is through the equivalent hysteresis damping ratio judgment, that the energy dissipation capacity of the SRC column of symmetric configuration steel is the ordinary concrete column energy dissipation capacity’s3～4times, this also explain that the seismic performance of this component is good.(2)The restoring force model is the relationship between force and displacement in repeated load,it reflects the recovery ability of the original deformation in the unloading,which is the foundation of the nonlinear analysis structure. This paper put forward P-Δ restoring force model, which suitable for the study of the SRC column of symmetric configuration steel, this model by stiffness degradation, three line skeleton curve model and the hysteresis of rules. Because of the specimens are asymmetrical, making the hysteresis curves’s plus or minus are asymmetry, thus skeleton curves are also asymmetric, and the model based on the test data, so that the skeleton curve model is also asymmetrical. The proposed restoring force model with linear simplified could basically better agreement with outsourcing skeleton curve, this model for the SRC column of symmetric configuration steel has very good reference value in the elastoplastic response analysis.