Behavior of shear studs in steel frames with reinforced concrete infill walls

Abstract

This paper reports on the behavior of headed shear stud connectors for use in steel frames with partially restrained connections and reinforced concrete infill walls, attached compositely to the steel frame around the perimeter of each wall panel (S-RCW system), subjected to seismic loading. In infill walls, the shear connectors lie in the plane of the concrete panel, which results in different behavior from studs in composite beams, for which the majority of past research has been conducted. In particular, shear connectors in infill walls are subjected to axial tension and compression forces due to sidesway and overturning of the S-RCW system, are influenced by the parallel edges of the wall, and are subjected to cyclic forces. An experimental program was developed to quantify the strength and deformation capacities of shear studs for use in S-RCW infill systems addressing the above issues, and to verify existing AISC, PCI, ACI, and Japanese design equations. A modification of the classic push-out test setup was made to accommodate the application of cyclic shear loading and axial tensile loading. Two different steel reinforcement configurations were used, one providing little confining reinforcement around the shear studs, and the other utilizing a steel reinforcement cage to provide ample confinement to the shear stud.