Cyclic behavior of RC beam-column joints strengthened with FRP systems

This paper presents the results of an experimental campaign performed at the Laboratory of Materials and Structural Testing of the University of Salerno (Italy) with the aim to investigate the seismic performance of RC beam-column joints strengthened with FRP systems. The complete test matrix includes eight full scale specimens designed to be representative of existing exterior beam-column subassemblies with inadequate seismic details. Of these, six were strengthened by using different FRP systems while the remaining ones were used as benchmarks. Once damaged, some specimens were repaired with FRP systems and re-tested. Tests were performed in displacement control by subjecting the specimens to cyclic excitation, whereas the axial load on the column was kept constant and equal to about 300 kN. Test results have provided useful information on the adopted strengthening systems in terms of strength, ductility and energy dissipation capacity. In particular, the results have allowed drawing some criticisms related to the design of the joint upgrading; the most suitable FRP configurations are also identified. Tests on repaired joints have confirmed the efficiency of the selected strengthening solutions. (C) 2013 Elsevier Ltd. All rights reserved.