Research On Repeated Tension And Compression Force Of Rolling Rib Sleeve Lap Connection And Seismic Performance Of Shear Wall

For the vertical reinforcement connection mode of prefabricated shear wall structure system,a new connection method called rolling rib sleeve lap connection has been proposed by the research group of Harbin Institute of Technology.In the previous research,a batch of unidirectional tensile tests of grouting sleeves have been carried out,and the connection performance of the sleeves and the unidirectional force mechanism of the overlapping sleeves have been studied.On this basis,this paper continues to carry out repeated tension and compression tests on the grouting overlap sleeve to study its mechanical performance under repeated tension and compression loads.In addition,this research applies this sleeve connection method to the vertical reinforcement connection of the fabricated shear wall specimens.In this study,three prefabricated shear walls were designed,and pseudo-static tests were carried out to study the seismic performance of the shear walls connected by rolling rib sleeves.The specific research content of this article is as follows:1.With three different steel bar diameters and two different lap methods as main parameters,18 grouting lap sleeve connection test pieces were designed,and the lap length is 10 d.High-stress repeated tension-compression and large-deformation repeated tension-compression tests were performed on this batch of specimens to verify the connection performance under both high-stress and large-deformation conditions.The test shows that the spiral rib sleeve lap connection steel bar meets the requirements for strength and deformation in the regulations after repeated high stress and large deformation repeated tension and compression.Analyzing the strain of the lap steel bars collected in the test,it is found that the stress-strain curve of the lap steel bar is similar to the curve obtained from the material property test,and the performance of the steel bar is fully utilized,indicating that the lap connection performance is good.2.In order to further study the reliability and feasibility of the application of rolling rib grouting sleeve lap connection in shear wall,three shear walls with longitudinal reinforcements of 12 mm,14mm and 16 mm were designed and manufactured.The paper proposes the method of joint grouting for the grouting connection between the shear wall and the bottom beam.The pseudo-static test was performed on the shear wall,and the load-displacement hysteresis curve,skeleton curve and the strain of connecting steel bars were obtained.It also analyzes the stiffness,ductility,energy dissipation capacity and connection performance of the lap steel bars of the shear wall specimens.Comparing the test results with the existing common cast-in-situ concrete shear wall test results of the research group,it is found that the seismic performance of the precast shear wall is close to that of the cast-in-situ shear wall.In addition,the performance of the lapped longitudinal ribs is fully exerted,and this connection method is reliable.3.Based on the repeated tension and compression test,the pseudo-static test of the shear wall and the one-way tensile test research carried out by Ma Fujin and Dai Linyao,the overall evaluation of the proposed grouting sleeve lap connection performance is carried out.In addition,the influence of design parameters such as lap length,lap method,and inner wall structure of the sleeve on the performance of the sleeve is explored.