Beam-Column Joint Retrofitting With High Performance Fiber Reinforced Concrete Jacketing

The possibility of strengthening existing R/C structures with a new technique based on the application of a High Performance Fiber Reinforced Concrete jacket is investigated herein, with the aim of studying the effectiveness of this technique for seismic retrofitting. The results of a beam-column joint full scale test, simulating the behavior of an existing beam-column joint, are presented. The specimen has been subjected first to static loads and then to cyclic actions with increasing amplitude, up to failure. The effects of HPFRC jacketing on beam-column joint behavior are analyzed: the experimental results are compared to analytical evaluations of strength of the retrofitted elements according to the new Italian code, and to the response of the base elements. The test demonstrated that, with the application of a high performance jacket, it is possible to remarkably increase the bearing capacity of the column and the strength of the beam column joint, reaching also an adequate level of ductility with very little visible damage, thanks to the tensile strength contribution of HPFRC.