Strengthening of RC beam-column joints with SRP/SRG systems

The study presented in this paper investigates the feasibility of Steel Reinforced Polymer (SRP) and Steel Reinforced Grout (SRG) systems in improving the seismic performance of exterior RC beam-column joints. An experimental program was organized which includes eleven specimens representative of existing beam-column subassemblies with inadequate seismic details and made of medium-low concrete compressive strength. Of these, nine were strengthened by using different SRP/SRG layouts while the remaining ones were used as benchmark (unstrengthened member); once damaged, five specimens were also re-tested after being retrofitted with SRP/SRG. Tests were performed by subjecting the specimens to reversed cyclic forces applied at the main beam by keeping the column under a constant axial load. The preliminary results, presented herein, have provided useful information on the performance of the adopted strengthening systems in terms of strength, ductility and failure mode of test specimens.