Fatigue performance of perfobond shear connector in steel-concrete composite structure

In order to investigate the fatigue performance of perfobond shear connectors in steel-concrete composite structure, according to the structure characteristics of perfobond shear connectors used in steel-concrete composite structure for different bridges, with opening of steel plate, diameter of steel bar and depth of steel plate as influence parameters, 24 push-out specimens in 6 groups were designed and orthotropic tests with 3 parameters in 2 levels were carried out. Based on the ultimate bearing capacity obtained by static push-out test, cycle numbers of different specimens suffering different loads were determined. Relation curves of cycle numbers and residual relative slip between steel and concrete were founded and fatigue damage evolution of perfobond shear connectors was divided into three stages. The results show that fatigue damage evolution of perfobond shear connectors can be described by residual relative slip, and fatigue damage and fatigue lifetime of perfobond shear connectors are determined by residual relative slip under different loads.