TY - JOUR

T1 - Stability of steel columns strengthened under preload

T2 - Numerical study with experimental validation

AU - Wang, Sizhe

AU - Su, Qingtian

AU - Jiang, Xu

AU - Ghafoori, Elyas

N1 - Funding Information: This work was supported by the Shanghai Engineering Research Center of High Performance Composite Bridges [No. 19DZ2254200 ], Key Research Project of Guangdong Province of China [No. 2019B111106002 ], the Natural Science Foundation of Shanghai [No. 21ZR1466100 ], and the Fundamental Research Funds for the Central Universities of China . The first author also acknowledges the support of the China Scholarship Council (CSC). Publisher Copyright: © 2022 Elsevier Ltd

PY - 2022/10

Y1 - 2022/10

N2 - Steel structures are often strengthened under a preload, which is defined as the existing load on the structure during the strengthening process. This study aims to understand the preload effect on the stability of strengthened steel columns. A numerical study on steel columns strengthened by bolted steel profiles under a preload is presented. Finite element (FE) models are developed and verified using experimental results. Furthermore, a parametric study is conducted with 242 FE models on parameters, including the preload, strengthened section properties, column length, and bolt configuration. The numerical results indicate that the preload effect on the ultimate load capacity can be beneficial, negligible, or adverse, ranging from −17% to 8%. The preload effect is found to be dependent on the preload level, section geometry, steel properties, and column length. Subsequently, a prediction model is proposed, wherein the preload effect is expressed as a function of the preload level and normalized slenderness. The prediction model is validated by existing experimental results and found capable of providing practically accurate predictions.

AB - Steel structures are often strengthened under a preload, which is defined as the existing load on the structure during the strengthening process. This study aims to understand the preload effect on the stability of strengthened steel columns. A numerical study on steel columns strengthened by bolted steel profiles under a preload is presented. Finite element (FE) models are developed and verified using experimental results. Furthermore, a parametric study is conducted with 242 FE models on parameters, including the preload, strengthened section properties, column length, and bolt configuration. The numerical results indicate that the preload effect on the ultimate load capacity can be beneficial, negligible, or adverse, ranging from −17% to 8%. The preload effect is found to be dependent on the preload level, section geometry, steel properties, and column length. Subsequently, a prediction model is proposed, wherein the preload effect is expressed as a function of the preload level and normalized slenderness. The prediction model is validated by existing experimental results and found capable of providing practically accurate predictions.

KW - Bolting

KW - Buckling

KW - Finite element method

KW - Preload

KW - Stability

KW - Strengthening

UR - http://www.scopus.com/inward/record.url?scp=85135838458&partnerID=8YFLogxK

U2 - 10.1016/j.jcsr.2022.107440

DO - 10.1016/j.jcsr.2022.107440

M3 - Article

AN - SCOPUS:85135838458

VL - 197

JO - Journal of Constructional Steel Research

JF - Journal of Constructional Steel Research

SN - 0143-974X

M1 - 107440

ER -