Seismic performance of steel fiber reinforced coal gangue concrete beam‐column joints

To investigate the seismic performance of Steel fiber‐reinforced coal gangue concrete (SFCGC) joints, six specimens of SFCGC joints were tested to investigate the effects of coal gangue replacement rate (CGRR) and steel fiber volume content (SFVC) on the failure modes of the SFCGC joints, the hysteresis curves, the displacement ductility, the shear deformation, the energy consumption, stiffness degradation, and bearing capacity. The study analyzed the cracking and failure trends of the specimens by comparing the results obtained through the digital image correlation (DIC) technique with conventional observations. The test results show that the failure mode of SFCGC joints is similar to that of steel fiber‐reinforced normal concrete (SFNC) joints. Under the same CGRR, the addition of steel fibers effectively inhibited the development of cracks in the joints, and the crack load and ultimate load increased by up to 45.4% and 47.4%, respectively. Finally, a computational model is proposed to determine the shear capacity of SFCGC joints, which was able to predict the bearing capacity of SFCGC joints adequately.