DOUBLE-HEADED STUDS AS SHEAR REINFORCEMENT IN BEAM-COLUMN JOINTS UNDER SEISMIC LOADS

Department of Civil Engineering, University of Calgary, Alberta, Canada

The Current ACI and CSA code provisions recommend large amount of shear reinforcement for reinforced

concrete beam-column joints in the form of closed hoops and cross ties to ensure confinement of the joint

concrete core. The closed hoops, in addition to the anchorage length of the beam bars, cause significant steel

congestion. In this research, double-headed studs are proposed as shear reinforcement in lieu of

conventional closed hoops and ties. Four full-scale beam-column joint specimens were tested under cyclic

loading. The first specimen was designed without shear reinforcement in the joint and used as sheardeficient

control specimen. The second specimen was designed according to the Canadian Code provisions

and the joint was reinforced with closed hoops and cross ties. The joints of the remaining two specimens

were reinforced with two different amounts of double-headed studs. The proposed detail of headed studs

proved to be a viable option for reinforcing exterior beam-column joints. In comparison with the shear

deficient-joint, the two specimens reinforced with double-headed studs exhibited considerable enhancement

in the behaviour, in terms of strength, ductility, energy dissipation, and joint contribution to the lateral drift.