Experimental Research On Pull-out And Interface Shear Resistance Of Box Connector On High-rise Structure

Housing industrialization has become the development trend of our countryin the future.Precast concrete shear wall structure is a housing industrialization structure system that conforms to China's actual conditions.For the precast concrete shear wall structure,the reliable connection between the horizontal seams of the prefabricated wall between the upper and lower layers is the key to ensure the integrity of the prefabricated shear wall structure.This article takes the high-rise prefabricated shear wall residential building constructed by Broad homes industrial co.Ltd as the engineering background,taking the method of prefabricated shear wall,size and reinforcement as the basis for specimens design,the experimental study on the pull-out and interface shear resistance of high-rise box connectors was conducted.(1)In this paper,the static loading method is used to complete the drawing test of the box connector.The failure modes and mechanical characteristics of the box connectors were studied.The results show that the failure mode of the specimen is broken for the upper drawing bar,the bonded anchorage performance of the high-rise box connector is good when working together with the concrete.The existing box connector has some optimization space,and combined with ANSYS finite element analysis,gives an optimized solution of the existing box connector.(2)In this paper,taking the number of boxes,interface characteristics,axial pressure and load eccentricity as the test parameters,static tests on the shear performance of 10 specimens of high-rise box connections used for precast concrete shear wall structure were conducted.The failure modes,bearing capacity,and the effect of various test parameters on the shear capacity of the interface were analyzed.The test results show that all the specimens are subject to shear failure,and the interfacial shear capacity is mainly provided by the interface friction force and pinning effect of the shear reinforcement.The force process of the horizontal joint interface can be divided into micro-slip stage,slip stage,descent stage and residual stage.(3)Based on the results of shear tests,the existing method for calculation of shear bearing capacity of the interface is compared and analyzed from the aspects of shear mechanism,resistance source,applicable conditions,etc.Comparing with the test results,the calculation method of the shear capacity suitable for the horizontal joint interface of high-rise box connection was selected.In order to study the interfacial shear behavior under composite stress,the influence of axial pressure and interface bending moment on the shearcapacity is further discussed,and the calculation method of shear capacity when the horizontal joint interface is applied to the bending moment is given.,and a calculation example is carried out.Based on the results of the experiment and analysis,a shear wall structure using high-rise connection was checked and analyzed.The results show that the pullout resistance and the shear strength of the horizontal interface can satisfy the requirements.