The Study On Hysteretic Behavior Of Recycled Aggregate Concrete Filled Steel Tube

The reuse of waste concrete has been paid more and more attention by scholars and experts due to environmental problems,but the mechanical property of recycled aggregate concrete is not as good as that of ordinary concrete,the recycled aggregate concrete structure is also poor compared with the ordinary concrete structure,which limits the application of recycled aggragate concrete in practice.Recycled aggragate concrete filled steel tube,which is made up of recycled aggregate concrete,which is used for cleaning,sorting and recycling construction waste,not only can make up for the shortcomings of recycled aggregate concrete,but also can enhance the bearing capacity of steel pipe.This new type of structure is helpful to alleviate the crisis of resources,and provides a new method for the disposal of construction waste.At present,the domestic and foreign scholars on the research of recycled concrete filled steel tube structure mainly focus on the axial compression performance,and the seismic performance is not much.Based on this,this paper studies from the following aspects:(1)This paper designs 6 thin-walled recycled aggregate concrete members(diameter 219mm,thickness 3.5mm),the axial compression ratio is the main parameters,the axial compression ratio is set to 0.2,0.4,0.6,the hysteresis curve of the specimen was obtained by experiment,and the skeleton curve and stiffness degradation curve are analyzed and compared.The equivalent viscosity coefficient and ductility coefficient of the specimen are calculated,which can reflect the deformation capacity and energy dissipation capacity of the specimen.The results show that:with the increase of axial compression ratio,the deformation capacity of the specimens is weakened,the ductility is poor,and the horizontal bearing capacity is improved.(2)The 6 components are simulated by ABAQUS finite element software,and the hysteretic curves and skeleton curves of the 6 components are obtained.The results of finite element analysis are in good agreement with the experimental results.At the same time,the influence of the steel ratio on the hysteretic curve of the specimen is simulated and analyzed,show that the steel ratio is also an important index of structural seismic performance,with the increase of steel ratio,the ductility and horizontal bearing capacity of the specimen have been improved.Finally,gives the calculation formula of recycled aggregate concrete filled steel tube P-delta model skeleton curve,hysteretic characteristic simulation,and the theory of horizontal bearing capacity and the experimental ones are compared.