Seismic performance of interior beam‐column joints using reinforced slag‐based geopolymer concrete
Yuguang Mao, Yunxing Du, Hyeon‐Jong Hwang, Jie Su, Xiang Hu, Yuzhong Liu, Caijun Shi
Abstract
Abstract Although geopolymer concrete (GC) is recognized as a green and low‐carbon material, GC structural members, particularly beam‐column joints, have been rarely studied. In the present study, eight reinforced GC joints and three reinforced concrete (RC) interior beam‐column joints were tested under cyclic loading. The test parameters were the concrete type, joint shear demand‐to‐capacity ratio, and axial‐compression ratio. The structural performance, including the failure mode, crack development, cyclic behavior of reinforced GC beam‐column joints, was evaluated. The test results showed that the cyclic behavior and crack development of the reinforced GC beam‐column joints differed from those of RC beam‐column joints. The increase of axial compression ratio improved the seismic performance of reinforced GC beam‐column joints with the joint shear demand‐to‐capacity ratio of 0.96–1.01. When the joint shear demand‐to‐capacity ratio was 1.54–1.61, the increase of axial compression ratio (0.1–0.3) improved the seismic performance, while the axial compression ratio of 0.5 was unfavorable because of significant joint shear damage. The applicability of the control conditions in the current design codes to the reinforced GC joints was evaluated. The control conditions of ACI 318–19 were applicable to the seismic design of reinforced GC beam‐column joints. On the other hand, the control conditions of GB50010‐2010 were not applicable because of the overestimated upper limit value of the joint shear demand‐to‐capacity ratio and axial compression ratio.