Seismic rehabilitation of beam–column joint using GFRP sheets

Techniques for upgrading reinforced concrete beam–column joints are proposed. The test specimens represent a typical joint that was built in accordance to pre-1970s’ codes. The objective of the rehabilitation is to upgrade the shear strength of these joints and reduce the potential for bond-slip of the bottom bars of the beam. Glass fibre-reinforced polymer (GFRP) sheets are wrapped around the joint to prevent the joint shear failure. GFRP sheets are attached to the bottom beam face to replace the inadequately anchored steel bars. Three beam–column joints are tested; namely, a control specimen and two rehabilitated specimens. The specimens are tested under quasi-static load to failure. The control specimen showed combined brittle joint shear and bond failure modes while the rehabilitated specimens showed a more ductile failure mode. A simple design methodology for the rehabilitation scheme is proposed.