Study On Static Performance Of Corroded Stud Connectors

The steel-concrete composite beam connects the steel and concrete components together through the shear joints,making full use of the advantages of high tensile strength and good plasticity of the steel and good compressive performance and economical advantages of the concrete material.Studs,the most commonly used shear connectors for steel-concrete composite beam structures,are critical factors in ensuring that steel and concrete work together.However,steel-concrete composite beams will be corroded by the natural environment in actual engineering,causing rusting of the stud connectors,which makes the research of corroded stud connectors necessary.In this paper,the artificial climatic environment accelerated corrosion method was used to simulate the natural climatic environment to corrode the test piece of the stud,and then the static test of the test piece was carried out by rust to study the change rule of the shear performance of the stud connection after corrosion.Moreover,the rusting introduction test was simulated by the finite element software ANSYS Workbench.The main research contents include:(1)A static loading test was performed on seven rusted test pieces and one uncorrupted test piece.The test results show that with the increase of corrosion time,the corrosion rate of the stud increases and the shear capacity of the stud decreases.(2)The test data was compiled to obtain the load-slip curve of each test piece.It was found that the initial shear stiffness of the test piece after corrosion was higher than that of the unrusted test piece,and the interface time was increased with the increase of the corrosion time.The increase in bond strength increases the initial shear stiffness of the test piece.(3)Based on the fitting analysis of the test results,the relationship between the ultimate shear capacity and the corrosion rate of the bolt is presented.(4)Using the cohesive zone model(CZM)based on fracture mechanics,the finite element model of the rusted pegs was introduced,and the simulation analysis was carried out.The comparison shows that the load-slip curves obtained by finite element method are The test curve is basically consistent.(5)In the finite element analysis of the rusted stud protruding test piece,a method for retrieving the cohesion model parameters from the feature points on the load-slip curve obtained by the test is proposed for the use of the cohesive force model.