Behavior of high-strength demountable bolted shear connectors in steel-concrete girders with prefabricated slabs

Composite structures with prefabricated concrete slabs and bolted shear studs can enhance the effectiveness and sustainability of construction. In this research, non-shrinkage cement grout is proposed to be filled between high-strength fully threaded bolt shear connectors and a prefabricated slab. Six static push-out tests are performed with different bolt dimensions and different pretension forces on the bolts to study the behavior of bolted shear studs. Finite element models for bolted shear connectors using ABAQUS/Explicit solver are developed, and they matched well with experimental results. Moreover, a Parametric study is conducted to investigate the effects of grout strength, bolt diameter, length-to-diameter ratio, bolt preloading, and bolt material type on the performance of shear connectors. Finally, the results of the parametric analysis are compared to the current design codes and previous researches and more precise equations for predicting the capacity and stiffness of bolted shear studs are proposed.