Experimental study of a reinforced concrete bridge pier strengthened with HPFRC jacketing

As a consequence of material degradation, increasing traffic loads and seismic actions, a large number of existing reinforced concrete bridges are no longer safe and may represent a risk for human lives and for the robustness of the road network. Replacement of these bridges is often not practical given the cost of demolition and rebuilding in addition to the social costs of traffic interruption. As an alternative to the replacement of the entire structure, the service life of a bridge can be extended by adopting reliable strengthening techniques. Among these strengthening techniques is High Performance Fibre Reinforced Concrete (HPFRC) jacketing, which was experimentally investigated in this research project. The mix design of HPFRC was studied with the goal of producing a material with enhanced mechanical performance as well as excellent rheology. In this study, the bridge pier studied was subjected to cyclic horizontal loads both before and after strengthening, up to failure. Experimental results show that the HPFRC jacketing remarkably increased the bearing capacity of the pier as well as its ductility. The jacketing also enhanced the structural response in terms of crack control, which significantly governs the structural durability.