Finite Element Analysis And Experimental Study On Seismic Performance Of New Type Precast Composite Shear Wall With Concealed Bracings And U Type Steel Bar

Precast composite shear wall is a kind of building structure system which is introduced from Germany and suitable for our country.The practical application of this structure system mainly includes design,prefabrication production,transportation and on-site assembly construction,which makes this system has the advantages of industrialization and standardization.Hence,the precast composite shear wall system is not only green,energy saving and environmental protection,but has reliable construction quality and a shorter construction period,which can reduce the comprehensive cost.In recent years,precast composite shear wall system has been actively researched and promoted with the development of housing industrialization,while there are still some difficulties in the application of this construction system.When precast composite shear wall system is used in high-rise buildings,the walls may be so thick that a mass of plain concrete need to be cast in the cavity,which will lead nonuniform stress distribution.In addition,horizontal connections between level structures and vertical connections between vertical structures are relatively weak,which may severely influence the integrity and seismic performance of the structure.All these problems make the use of precast composite shear wall system get restricted,and its development is inevitably limited.At present,the precast composite shear wall structure promoted in China adopts German technology.The precast composite shear wall panels are connected by two concrete shells inside and outside through lattice reinforcement and are prefabricated at the factory.In the production process,the steel skeleton is first made,a layer of concrete shell is poured and then poured,and the concrete shell on the other side is poured.The production process is relatively complicated,and the superimposed shear wall wall is self-sustaining,and the long-distance transportation is difficult,and at the same time,During the on-site construction process,due to the large weight,large-scale lifting equipment is required,and the assembly process is cumbersome.In order to make the construction process of the laminated plate shear wall easier and more efficient,we tried to propose a new type of X-shaped steel plate concealed bracing superimposed shear wall with two independent prefabricated U-bar reinforced concrete slabs and middle pouring self-compacting concrete.At the same time,this paper combines experimental research and nonlinearfinite element analysis,systematically researches and analyzes the overlapped shear wall with concealed bracing.The main research contents are as follows:(1)A quasi-static test was performed on a self-compacting concrete shear wall with horizontal U-rib reinforcement and a vertical U-bar self-compacting concrete shear wall with a dark steel plate with a dark support.,Systemically compares the failure modes,hysteresis curves,skeleton curves,bearing capacity,ductility,stiffness degradation,and energy consumption of the two specimens.The results show that compared with the horizontal U-rib superimposed shear wall,the vertical U-rib superimposed shear wall has basically the same crack distribution and failure pattern as the former,and all of them are bending shear failure,bearing capacity and various earthquake resistances.The indicators are also equivalent to the former and have good seismic performance;U-shaped rib structure is reasonable,there is no vertical cracks and relative misalignment,the sample shows a good integrity,and the prefabricated wall and the cast-in-place wall can be coordinated.Force.(2)Using ABAQUS software to simulate the mechanical behavior of the interface between the old and new concrete in shear wall specimens using a bidirectional nonlinear spring,and to establish a finite element model to simulate the axial compression and horizontal monotonic load of the two shear wall specimens.Common performance.The analysis shows that the results of the finite element calculation are well fitted to the experimental results,which verifies the rationality of the modeling method and parameter selection in this paper.(3)Based on the effectiveness of the finite element model,the ratio of axial compression ratio,the ratio of the ratio of dark column reinforcement,and the ratio of steel support to concealed bracing are used as variables.