Study On Seismic Performance Of Precast SRCT Shear Wall Structures With Horizontal Joint Connections

Shear wall is one of the most commonly used component in high-rise buildings,which is used as the primary part of the building's lateral force-resisting system.With the continuous improvement of requirements for construction quality,production efficiency,production environment,energy saving and emission reduction,cast-in-situ reinforced concrete(RC)structures usually cannot meet these requirements well.At present,the steel-reinforced concrete composite shear wall and the single steel plate concrete composite shear wall have a complicated structure.The concrete distribution rebar at the location of shear wall need to be tied on site and the construction efficiency is low.Most of the current double-steel concrete shear wall and the bundled lipped channel-concrete composite wall have exposed steel olates,which require professional fire protection and anti-corrosion treatment.This approach increases the construction cost.At the same time,horizontal joints inevitably exist in prefabricated shear walls,and the mechanical properties at the joints directly affect the reliability of the overall structure.In view of this,author puts forward a steel-concrete composite tube(SRCT)shear walls of horizontal joint connection.The steel-concrete composite tube is generally prefabricated in the factory.The SRCT component connects the horizontal and vertical joints at the project site by dry connection,and then the concrete is poured inside the SRCT to form the SRCT shear wall structure system.It has the advantages of high bearing capacity,fast construction speed,easy quality detection and good corrosion resistance.The author studies the seismic behavior of steel-concrete composite tube(SRCT)shear walls of horizontal joint connection through experiment study and theoretical analysis.The main research contents and achievements are as follows:(1)An experimental program was conducted on the full-scaled models of SRCT shear walls to study the seismic behavior of steel-concrete composite tube(SRCT)shear walls with horizontal joint.Performance of the test specimens was evaluated in terms of failure mode,hysteretic curves,ductility,stiffness degradation and energy dissipation capacity,et al.The lateral deformation and the strain of the key part of the wall have been analyzed.(2)Though the test data,based on the superposition theory and the assumption of flat section,the calculation method of SRCT shear wall normal section bearing capacity is proposed.By comparing with the test results,the accuracy of the calculation method is verfied,indicating that the calculation methood can be used in the calculation of the SRCT shear wall bending capacity.(3)Based on the analysis of tests data of SRCT shear wall,the calculation method of shear load capacity of SRCT shear wall is proposed and the calulation result is consistent with the test phenomenon.The calculation method refers to the relevant calulation methods of shear load capacity of shear wall in Code for Design of Composite Structures.Since the shear-span ratio of the test specimens is 1.6 and the failure mode of the shear wall is mainly bending failure.Therefore,the accuracy of the proposed method for calculating the shear capacity of oblique sections still needs to be verified by a series of tests on low shear-span ratio SRCT shear walls.(4)The numerical simulation on steel-concrete composite tube(SRCT)shear walls with horizontal joint was conducted with the nonlinear finite element software,and the theoretical analysis results were verified with test results.Thereafter,the parametric analysis has been conducted to study the influences of seismic performance,such as the axial compression ratio,strength of steel,concrete strength,the thickness of the steel plate,piercing bar spacing and diameter.(5)The welding structure of each part of a steel-concrete composite tube(SRCT)shear walls of horizontal joint connection is analyzed.Reliable measures be taken to improve the welding quality of thin steel plate to avoid welding damage and ensure the seismic performance of the shear wall.As a new type of steel-concrete composite shear wall,this paper analyzes the seismic performance of the assembled SRCT shear wall with horizontal connection nodes through experimental research and theoretical research,and proposes the SRCT shear wall bearing capacity calculation model.The research results can provide reference and basis for the study and application of SRCT shear wall structure.