EXPERIMENTAL AND THEORETICAL RESEARCH ON RCFT BEAM-COLUMNS FABRICATED WITH Q420B HIGH-STRENGTH STEEL SUBJECTED TO ECCENTRIC LOAD

This study is motivated by the widespread use of concrete - filled tubular (CFT) columns and the increasing use of high strength steel (HSS). However, due to limited research, HSS was not extensively utilized in rectangular concrete - filled tubular (RCFT) columns. In this paper, the behavior of RCFT columns manufactured with Q420B HSS subjected to eccentric load was studied through the method of experimental and finite element (FE) analysis. The eccentric compression test was conducted on seventeen specimens with different concrete strength, width - to - thickness ratio, aspect ratio, and excentricity ratio. It obtained and discussed failure modes, load-vertical displacement curves, load-lateral deflection curves, and variations in strain. ABAQUS software developed nonlinear FE models based on an experimental program. Several specifications, including EC4, AISC360, AIJ, GB 50936-2014, and DB 29-57 for predicting the ultimate capacities of RCFT columns under excentric loading, were discussed through comparison with experimental results. The proposed approaches were also verified to be reasonably conservative for practical design with the experimental results. Copyright (C) 2020 by The Hong Kong Institute of Steel Construction. All rights reserved.