Reinforced concrete (RC) moment resisting structures built during the early 1950’s through 1970’s are vulnerable for earthquake loads due to lack of adequate strength and ductility. Beam-column joint, the common region between the framing beams and columns, is a crucial…
Reinforced concrete (RC) moment resisting structures built during the early 1950’s through 1970’s are vulnerable for earthquake loads due to lack of adequate strength and ductility. Beam-column joint, the common region between the framing beams and columns, is a crucial zone to ensure global response of such moment resisting structures. Many of such structures all over the world need immediate measures for upgrading their performance level to withstand the seismic loading effects. Several methods have been attempted over the years by many civil engineers and practitioners for strengthening of deficiently detailed RC beam-column joints. In this paper, an emphasis has been made to understand the joint vulnerability against lateral loads and review of various retrofitting methods and their efficiency for RC beam-column joints. Further, some experimental investigations on the performance of joints strengthened with haunch elements have been reported. The numerical studies show that at the location of 0.2 times the span of the beam from the center of the column at a orientation angle of 450 produced the highest reduction of shear stress in the joint region. The experimental investigations show that the RC beam-column joints designed with haunch elements exhibited better performance in terms of significant shear strength, ductility, less stiffness degradation and energy absorption under cyclic loading.