Calculation Model And Seismic Performance Analysis Of Semi-Rigid Steel Frame–CFS Infilled Wall Structure

In recent years,in order to solve the energy shortage,ecological deterioration,environmental pollution and other problems,the energy-conservation,environmental-protection,green and low-carbon structural forms have been vigorously promoted in China.And with the concept of "carbon neutral" and "new rural construction" put forward,the prefabricated building gradually become the inevitable trend of the construction industry development.As an indispensable part of prefabricated building,prefabricated wall has great developing space and prospect.A new type of prefabricated CFS infilled wall,which is formed by filling the lightweight polymer into the cold-formed thin-walled steel(CFS)frame exhibit the advantages of high strength,insulation,fire prevention and earthquake proof,and high degree of industrialization.The new type of wall has been used in low-and multi-storey prefabricated buildings.However,due to the limitation of the height and span,the walls could be adopted to the high-rising buildings difficultly.Therefore,in order to promote the application of light CFS infilled wall in high-rise buildings and realize the seismic performance of the light CFS infilled wall as a lateral force resistant member,this paper introduces the CFS infilled wall into semi-rigid steel frame structures.And the main research work is listed as follows:(1)Based on the relevant calculation theories,the calculation formulas for lateral stiffness and shear bearing capacity of semi-rigid steel frame–CFS infilled wall structures were proposed,and validated by test data.The comparison verified the accuracy of the formula and provided a specific theoretical basis for this structure in practical application.(2)Based on the SAP2000 software,the Pivot model was used to simplify 4 CFS infilled walls,and the relationship formula of P-Δ skeleton curve of walls is deduced;meanwhile,the corner spring element was used to simplify the connection between the 3 rectangular steel pipe columns and the H-shaped steel beam high-strength blind bolts.And on the basis of the simplified CFS infilled wall and semi-rigid joints,a nonlinear simplified analysis model of semi-rigid steel frame–CFS infilled wall structures were established.Additionally,hysteresis curve and load-displacement skeleton curve were applied to verify the rationality of simplified methods for CFS infilled walls and semi-rigid joints.The rationality of the nonlinear simplified analysis method was verified through experiments.Then this method would provide a reliable foundation for the subsequent seismic performance analysis.(3)With reference to the archetypes models of a ten-story three-span semi-rigid frame and three CFS infilled walls–semi-rigid steel frame structures were established.The parameter of wall layout was explored Based on the base shear,vertex displacement,story drift,etc.Under different waterproof standards,the dynamic response of structures under the elastoplastic time history analysis is learned.(4)On the basis of the seismic design method,the structural seismic performance evaluation index was proposed,and the capacity spectrum method was used to evaluate the seismic performance of structures.The results showed that the elastoplastic deformation of the structure under rare earthquakes meet the limit of inter-story displacement,and had sufficient ductility to achieve the performance goal of "preventing collapse".