Stud-concrete interactional model of shear connectors in steel-concrete composite structures

A theoretical calculation method, named stud-concrete interactional model, of load-slip relationship of stud shear connectors in composite structures is presented. This model has been developed based on the elastic foundation beam theory and considers the different stress states of the concrete around studs during the damage process. Two important stud-concrete interaction parameters, called equivalent spring stiffness and yielding slip, are introduced for the first time to quantify the shear contribution of concrete and the relative slip between stud and concrete, respectively. The range of yielding slip has been determined based on a force-flow model and a finite element model. The proposed stud-concrete interactional model has been utilized to derive the load-slip formula considering the elastic, elastoplastic, and plastic stages of stud shear connectors. Experimental results show that the proposed formula are valid and outperform existing formulas. This paper offers new insight into the shear behavior of stud shear connectors.