Experimental study on bond‐slip constitutive relation of SSSCFST columns. (6th April 2021)

• Record Type: Journal Article
• Authors: Yu, Feng; Fang, Yuan; Niu, Kang; Zhang, Yang; Chen, Taiyao
• Is Part Of: Structural concrete. Volume 22:Number 4(2021)
• Page Start: 2338
• Page End: 2357
• Publication Date: 2021-04-06
• Subjects: bond‐slip -- concrete filled steel tube -- constitutive relation -- diameter‐thickness ratio -- self‐stressing -- steel slag; Reinforced concrete -- Periodicals; 624.1834
• DOI: 10.1002/suco.201900546
• Languages: English
• ISSNs: 1464-4177

Abstract

Abstract: This paper presents the bond‐slip tests of six self‐stressing steel slag concrete filled steel tubular (SSSCFST) columns. The effects of the self‐stressing (expansion ratio) of steel slag concrete (SSC), diameter‐thickness ratio and confinement factor on bond‐slip behaviors are analyzed, and the bond‐slip mechanism of the SSSCFST columns is revealed. According to the static equilibrium condition, an analytical model for predicting the ultimate inter‐facial bond strength is put forward considering the influence of self‐stressing between steel tube and SSC, and a simplified formula for conveniently evaluating the bond load of the SSSCFST columns is suggested based on the regression analysis of test data. In addition, a bond‐slip constitutive model of SSSCFST columns is established, and the distribution law of the longitudinal compressive stress, inter‐facial bond stress, and relative slip are obtained. Three formulas for estimating the bond slip stiffness, the slip value corresponding to the ultimate bond strength, and the bond stress of load invariant stage are proposed respectively depending on the regression analysis of test data. Eventually, a simplified three‐stage bond‐slip constitutive relation of SSSCFST columns is suggested.