Research On Static Characteristics And Fatigue Performance Of Steel-Concrete Composite Structure Shear Connectors

Steel-concrete composite structure is developed as a new structure based on reinforced concrete structure and steel structure.Because it can reduce the amount of materials,speed up the construction process,and improve the overall performance of the structure,it has been widely used in engineering practice once it appeared.As the key component connecting the concrete slab and the steel beam,the shear connector has its own static performance,namely the ultimate shear resistance and fatigue resistance,which are very important for the entire composite structure.On the basis of theoretical analysis,this article combines numerical simulation methods to study the shearing ultimate bearing capacity and fatigue performance of shear connectors,the main contents are as follows;(1)This article first briefly describes the working principle and failure mode of stud connectors,proposes test methods for stud shear capacity and related concepts of stud load-slip curves,and makes fatigue-related theories,especially the fatigue SN curve.The detailed description will provide theoretical guidance for the subsequent FEM simulation launch test and the modeling and analysis of the fatigue life of the connectors in the real bridge.(2)Based on the test method for studying the shear bearing capacity of shear connectors,the push-out test model of stud connectors was established using the finite element software ABAQUS,and the change of the load-slip curve of the stud connectors during the whole push-out test was studied.In the case of changing the size parameters of the peg itself,it was found that the change in diameter had a greater impact on the ultimate bearing capacity of the peg itself,while the change in height had a smaller effect on the ultimate bearing capacity.(3)By establishing a refined partial solid bridge finite element model,the effects of studs on the fatigue performance of the studs concerned in the real bridge under different factors such as diameter and arrangement spacing were studied,and the equivalent constant amplitude stress amplitude of the studs was found at There is a significant increase when the two parameters are changed,but the equivalent 2 million times of constant amplitude stress amplitude of each concerned part is less than the corresponding 90MPa in the SN curve,and the fatigue performance of the stud is good and fully meets the design of 100 years.Service life requirements.