Shearing performance of concrete exterior beam-column joints with HRB400E reinforcement

Abstract:

To study the shearing performance of concrete exterior beam-column joint with HRB400E reinforcement, we designed nine specimens based on orthogonal test method and conducted shearing test, which takes concrete strength, horizontal reinforcement anchorage arrangement, and reinforcement ratio as the main research parameters. Test results show that beam end bending failure and joint core shear failure were common failure modes of specimens, but bending anchorage arrangement could effectively reduce the number of cracks in the joint core. Among the three parameters, concrete strength had the most influence on the shearing deformation of the joint core, and as the concrete strength grade increased, the shearing deformation angle at the initial crack decreased. The anchorage arrangement of the horizontal bars had the most influence on the shearing deformation of joint core at the ultimate state, and shearing deformation angle reached the minimum value when 90° bending anchorage arrangement was adopted. The ratio of longitudinal reinforcement to beam had the greatest influence on the horizontal shearing force of the joint, and the horizontal shearing force increased with the increase in the reinforcement ratio. The primary and secondary relations of the parameters and corresponding changing trends were analyzed by using the orthogonal test principle combined with the mathematical statistics theory of range and variance.