Seismic Performance of Interior and Exterior Beam–Column Joints in Recycled Aggregate Concrete Frames

Abstract

The failure of beam–column joints in RC frame buildings induced by a strong earthquake can lead to the collapse of buildings. Therefore, numerous experimental studies have been carried out on beam–column joints made with natural aggregate concrete (NAC). However, only a few experimental tests have been conducted on recycled aggregate concrete (RAC) beam–column joints. This paper presents an experimental investigation of the seismic behavior of various types of RAC beam–column joints. A series of five RAC beam–column joint specimens, including three interior joints and two exterior joints, were tested under quasi-static cyclic loading and their behaviors were evaluated in terms of strength, stiffness, cumulative energy dissipation, damping ratio, and damage indexes at different load steps. The influence of joint type, column axial compression level, stirrup ratio in the joint panel, and longitudinal reinforcement ratio on the seismic performance of RAC joints was evaluated. The validity of RC joint shear strength models proposed by different building codes to predict RAC joint shear strength were examined by comparing the experimental shear strength values with analytical results.