Performance comparison of beam-column joints with different concretes

Abstract

With the development of concrete materials, high strength concrete (HSC) and fiber reinforced concrete (FRC) are more and more used in reinforced concrete frame structures. This paper collected the test results of normal concrete (NC), HSC and reactive power concrete (RPC) beam joints. The performances of different concrete joints were compared and analyzed from two aspects of failure process and characteristics and shear deformation. The results showed that the ratio of through-crack load to shear capacity of NC joints is about 0.75-0.80, while that of RPC joints through-crack is close to shear capacity. The randomly distributed steel fibers of RPC like dispersed steel bars can effectively restrain the development of oblique cracks in the core area of joints. When the ultimate load is reached, the average shear angle of NC joints is much larger than that of RPC and steel fiber reinforced concrete joints. The small deformation of joints ensures the stiffness of RPC and steel fiber reinforced concrete joints. However, because there is no coarse aggregate in RPC, the occlusal interaction between the two sides of oblique cracks in the core area of RPC beam-column joints is obviously lower than that of NC joints.