Experimental and analytical study on eccentric compressive behavior of concrete columns strengthened with high-strength reinforcement of HRB600

Abstract

This study examines the influence of initial eccentricity, volume stirrup ratio, and the strength of longitudinal reinforcement and stirrup on the eccentric compressive performance of concrete columns strengthened with HRB600-high-strength-reinforcement. Ten concrete columns are tested under eccentric compression. The compressive mechanism evaluates and compares the failure characteristics, load-deformation curve, reinforcement strain, and eccentric compression performance. As part of the numerical study, the finite element modeling of OpenSees is used to predict the response of HRB600 specimens under eccentric compressive loading, and parametric analysis is subsequently conducted. The research findings illustrate that HRB600 longitudinal reinforcement can yield in tension and compression with large eccentricity when approaching the ultimate bearing capacity state. After normal strength longitudinal reinforcement is supplanted, the reinforcement amount is saved. Lastly, semi-empirical models have been proposed to predict the compressive performance of concrete columns with high-strength reinforcement.