Experimental Study on the Seismic Behaviour of Strengthened Concrete Column-Beam Joints by Simulated Earthquake

A total of five repaired column-beam joints (C-BJs) strengthened by basalt fiber reinforced polymer (BFRP) had been pre-damaged under cyclic loads in order to study on the seismic behavior. The experimental study including pre-damage, rehabilitation and re-test under cyclic loads concentrated on the effect on different levels of pre-damage and epoxy injection. Through the experimental data, ultimate load-carrying capacity, ultimate displacement, ductility, hysteresis curves and dissipative ability, the following conclusion was drawn: it is indispensable for the load-carrying capacity of frame beams to contribute to slab. The repaired C-BJs can reach or even exceed the level of their ultimate load-carrying capacity and original seismic performance before pre-damage. The load-carrying capacity and bond-slip behaviors can be improved by the BFRP in the repaired C-BJs. Concrete columns can be effectively confined to the expansion and deformation. The failure mode of strong beam and weak column was changed into strong column and weak beam after rehabilitations. The study indicated that the method of BFRP-reinforced pre-damaged concrete column-beam joints was reasonable and effective. (C) 2011 Published by Elsevier Ltd.