Seismic performance of corroded non-seismically and seismically detailed RC beam-column joints rehabilitated with High Strength Fiber Reinforced Concrete

The experimental investigation was undertaken to restore the seismic performance of the corrosion-damaged beam-column joint (BCJ) rehabilitated with High Strength Fiber Reinforced Concrete (HSFRC). A total of eight exterior beam-column sub-assemblages were cast following two types of reinforcement detailing as per IS 456:2000 and IS 13920:2016, respectively. Three specimens from each reinforcement detailing regime were subjected to three different levels of corrosion and thereafter rehabilitated with HSFRC. The hysteresis behavior, energy dissipation, stiffness degradation, crack patterns, and damage index of all rehabilitated specimens are analyzed and compared with the conventional specimens. Test results indicate that the replacement of damaged concrete with HSFRC can recover the strength of corrosion-damaged BCJ when the corrosion ratio is within 10 %. The peak load-carrying capacity and initial stiffness of rehabilitated specimens showed a significant increase up to 36 % and 84 % respectively, when compared to control specimens. The ductile detailing rehabilitated specimens showed up to 90 % higher equivalent viscous damping ratio than the non-ductile ones, exhibiting close stirrups arrangement superiority. Despite recovering the load-carrying capacity at initial drifts, the seismic performance of non-ductile and ductile rehabilitated specimens having 17.76 % and 20.32 % corrosion ratio were not recovered at higher drifts.