Experimental investigation on the effect of local debonding of longitudinal reinforcement on seismic performance of precast concrete columns

The influence of the local debonding of longitudinal reinforcement on the seismic performance of prefabricated column with the grouted longitudinal reinforcement in corrugated sleeves is investigated. A total of 10 precast concrete specimens and 1 cast-in-place concrete specimen were designed and tested. Important factors such as anchorage length, local debonding position, debonding length and axial compression ratio were considered. The seismic performance was evaluated under low cycle reversed loading tests, and the failure mode, hysteretic curve, skeleton curve, ductility performance, energy dissipation capacity and stiffness degradation of the specimens were obtained and analyzed. It is found that the hysteretic curve of the precast column with local debonded longitudinal reinforcement is fuller than that of the bonded precast column, and the ductility and energy dissipation capacity of the precast column with local debonded longitudinal reinforcements are significantly improved. The effects of the debonding length and position of the longitudinal reinforcements on the ductility, energy consumption and bending deformation of the precast columns are also discussed. This study is of great significance to improve the bearing capacity and seismic performance of prefabricated columns on the top of the independent foundation in practical engineering.