Seismic performance of reinforced concrete beam‐column joint made of post‐filling coarse aggregate concrete

Abstract

AbstractPost‐filling coarse aggregate concrete is a new type of green concrete that not only saves the cost of cementitious material, improves the strength, cracking resistance and durability of concrete, but also reduces the carbon footprint. In view of the lack of research on the seismic performance of post‐filling coarse aggregate concrete, this study designs eight interior beam‐column joint specimens made of post‐filling coarse aggregate concrete and three beam‐column joint specimens made of conventional concrete. It studies the influence of post‐filling coarse aggregate ratio, axial compression ratio and stirrup volume ratio of node area on the seismic performance of joint specimens. Through low cyclic reversed loading test, the failure process and the failure pattern, hysteresis curves, skeleton curves, ductility, stiffness degeneration, residual strength and residual displacement, and plastic hinge rotation of interior joints with post‐filling coarse aggregate concrete are analyzed. Test results show that the failure mode of post‐filling coarse aggregate concrete joints is similar to that of the conventional concrete joints. As the axial compression ratio increases, the seismic performance of the joints shows a trend of increasing first and then decreasing, and it reaches the peak when the axial compression ratio is 0.2. It also demonstrates that the seismic performance of the joints is increased by increasing the stirrup volume ratio of node area. Ultimately, under the same axial compression ratio, the seismic performance of the post‐filling coarse aggregate concrete is not significantly different from that of the conventional concrete. It proves that the reinforced beam‐column joint made of post‐filling coarse aggregate concrete could fulfill the comparable seismic performance as that of conventional concrete.