Pseudo-static Test And Finite Element Analysis Of Prefabricated Rectangular Concrete-filled Steel Tube Column RC Beam Frame Structure

In addition to the advantages of conventional frame structures such as high bearing capacity,good ductility,fatigue resistance and excellent seismic performance,the prefabricated concrete-filled steel tubular pillar-RC beam frame structure can also be constructed simultaneously,and the construction efficiency is high.At the same time,the precast component has the advantages of better material,durable and beautiful,economical and affordable,convenient transportation,and better construction quality,which reduces the waste of resources and environmental pollution compared with the traditional cast-in-place structure.In this paper,based on the subway parking lot of a railway transit project in Guangzhou City,combined with the test site conditions of a school,a new test component of a single-span single-storey prefabricated rectangular concrete-filled steel tubular pillar-RC beam frame was produced,a detailed pseudo-static test scheme was designed,and the seismic performance of the structure was analyzed by using the test method.On the basis of the test,a three-dimensional finite element nonlinear analysis model is established for the assembled rectangular concrete-filled steel tubular column-RC beam frame member with ANSYS.Based on the comparison between the simulated analysis results and the measured data,the validity of the finite element analysis results is verified.It provides some reference for the popularization and application of this kind of frame structure and further research.(1)Fabrication of test components and design of test scheme.Under the background of practical engineering and combined with the existing conditions,a test component of a single span single-layer prefabricated rectangular concrete-filled steel tubular column RC beam frame was manufactured.Based on laboratory instruments and equipment,a detailed pseudo-static test scheme is designed from the aspects of test device,loading scheme,test instrument and test content.(2)Analysis of test data.Based on the pseudo-static test of a single span single-storey prefabricated rectangular concrete-filled steel tubular pillar-RC beam frame structure,the failure state and hysteretic curves of the frame are obtained.The mechanical properties such as skeleton curve,ductility and energy dissipation capacity,strength degradation and stiffness degradation were analyzed.The experimental results show that the failure mechanism of the frame is "strong column and weak beam",the hysteretic curve of the frame is full of fusiform,the deformation capacity is good,the energy dissipation capacity is strong,the overall strength and stiffness degradation is slow,and the whole frame shows good plastic deformation capacity and seismic performance.(3)Finite element model verification.On the basis of the experiment,the analysis idea of finite element and the analysis method of nonlinear finite element are described briefly.The appropriate material constitutive and element type are selected,and the finite element model of the test frame is established with ANSYS finite element software.The boundary displacement constraint is added to the model,and the appropriate cyclic load scheme is applied.The theoretical curve obtained by calculation is compared with the experimental curve,and the overall agreement is good,which verifies the validity of the finite element model,and also shows the reliability of the model.The model can be used for in-depth study and parametric analysis.