Repair of seismically damaged RC columns through FRCM Composites

Repair of damaged RC elements have always been a topic of key interest in civil and structural engineering. The results of an experimental campaign investigating the behavior of two realscale reinforced concrete (RC) columns, initially seismically damaged through lateral cyclic loading then repaired through carbon fiber reinforced cementitious matrix (CFRCM) and subjected to the same test, are presented in this paper. Based on the damage observed on the control specimens, two repair techniques were adopted. For the less damaged specimen, the column base was confined through CFRCM jacket while for the more severely damaged element additional FRCM flexural reinforcement was embedded in the FRCM confinement jacket applied at the base. Both interventions aimed to restore the initial strength and ductility of the undamaged RC specimens. During the loading history, lateral fiber strains were monitored continuously in the confinement jacket. The test results are presented in terms of cracking pattern, load-displacement curves, ductility, energy dissipation and curvature development and show that FRCM composites can be effectively used to restore strength and ductility of RC columns previously damaged by cyclic lateral loading.