Using high-strength self-compacting concrete in reinforced concrete beam-column joints
The capability of self-compacting concrete (SCC) in flowing through and filling in even the most congested areas makes it ideal for being used in congested reinforced concrete (RC) structural members such as beam-column joints (BCJ). However, members of tall multi-storey structures impose high capacity requirements where implementing normal-strength self-compacting concrete is not preferable. In the present study, a commercially reproducible high-strength self-compacting concrete (HSSCC), a conventionally vibrated high-strength concrete (CVHSC) and a normal strength conventionally vibrated concrete (CVC) were designed using locally available materials in Christchurch, New Zealand. Following the guidelines of the New Zealand concrete standards NZS3101, seven beam-column joints (BCJ) were designed. Factors such as the concrete type, grade of reinforcement, amount of joint shear stirrups, axial load, and direction of casting were considered variables. All BCJs were tested under a displacement-controlled quasi-static reversed cyclic regime. The cracking pattern at different load levels and the mode of failure were also recorded. In addition, the load, displacement, drift, ductility, joint shear deformations, and elongation of the plastic hinge zone were also measured during the experiment. It was found that not only none of the seismically important features were compromised by using HSSCC, but also the quality of material and ease of construction boosted the performance of the BCJs.