Experimental Study On Shear Capacity Of Steel Bars At The Interfaces Of Prefabricated Concrete Structure

Due to the constructions of convenience,affordability and other features,prefabricated concrete structure is widely used both at home and abroad.However,the design system is not complete,especially for the using of beam-columns joint.Dowel action is the main resisting mechanism between the construction interfaces and joints.Shear bearing capacity of PC structure has a greater impact on the overall bearing capacity of the structure.To assure the safety of the PC structure,it is of great importance to study the shear capacity of steel bars at the interfaces of prefabricated concrete structures.In this paper,the shear behavior of reinforced concrete members is studied.Which includes:(1)Based on the investigate of the experimental method of dowel action the interface shear of steel bars and the direct shear test of steel bars are compared,and the steel direct cutting program is chosen in this study.Besides,the effect of different loading devices on the direct shear test of steel bars were explored.Finally,a multi-hinge linkage device is proposed for direct shear test of steel bars.(2)The direct shear tests of different test parameters are carried out.The shear bearing capacity,deformation performance and shear force transfer process of reinforced concrete connections interface under different failure modes are studied.The influence of axial damage and axial compression on the shear performance of steel were studied by the initial damage condition.Based on the test results,the correction formula of dowel action is established.(3)The acoustic emission signals generated by concrete under the action of load are collected and processed,and the acoustic emission characteristics such as acoustic impact count,energy count and ringing count are obtained.The analysis of the characteristic parameters is carried out to explore the development process and damage form of concrete internal,and the internal damage is visualized by means of sound source localization technology.