TY - JOUR
T1 - Numerical analysis and formulae for SCF reduction coefficients of CFRP-strengthened CHS gap K-joints
AU - Xu, Guowen
AU - Tong, Lewei
AU - Zhao, Xiao Ling
AU - Zhou, Haiming
AU - Xu, Fei
N1 - Funding Information:
The authors are grateful for the financial support from Shanghai Civil Engineering Peak Discipline Program of Shanghai Municipal Education Commission (No. 2019010301 ).
Publisher Copyright:
© 2020 Elsevier Ltd
PY - 2020/5/1
Y1 - 2020/5/1
N2 - The focus of this paper is on estimating stress concentration factor (SCF) reduction coefficients (ψ) of circular hollow section (CHS) gap K-joints strengthened with carbon fibre reinforced polymer (CFRP) sheets (CFRP-CHS K-joints), so that the SCFs can be calculated on the basis of the existing formulae for unstrengthened joints. Three-dimensional finite element models are developed for both CFRP-strengthened and unstrengthened CHS gap K-joints to calculate the SCFs, which are verified using previous test data. A parametric study is then carried out to explore the effects of various parameters (11 independent CFRP strengthening parameters and 5 basic geometric parameters describing the steel K-joints) on the efficiency of CFRP strengthening in terms of SCF reduction coefficient ψ. It is found that ψ is primarily affected by the CFRP relative reinforcement rates, the CFRP-to-steel tensile modulus ratios, the adhesive modulus, and non-dimensional geometric parameters. Through regression analyses, parametric formulae are finally developed for estimating ψ at six critical hot spots in CFRP-CHS K-joints under balanced axial loading. The proposed parametric formulae agree well with the experimental data.
AB - The focus of this paper is on estimating stress concentration factor (SCF) reduction coefficients (ψ) of circular hollow section (CHS) gap K-joints strengthened with carbon fibre reinforced polymer (CFRP) sheets (CFRP-CHS K-joints), so that the SCFs can be calculated on the basis of the existing formulae for unstrengthened joints. Three-dimensional finite element models are developed for both CFRP-strengthened and unstrengthened CHS gap K-joints to calculate the SCFs, which are verified using previous test data. A parametric study is then carried out to explore the effects of various parameters (11 independent CFRP strengthening parameters and 5 basic geometric parameters describing the steel K-joints) on the efficiency of CFRP strengthening in terms of SCF reduction coefficient ψ. It is found that ψ is primarily affected by the CFRP relative reinforcement rates, the CFRP-to-steel tensile modulus ratios, the adhesive modulus, and non-dimensional geometric parameters. Through regression analyses, parametric formulae are finally developed for estimating ψ at six critical hot spots in CFRP-CHS K-joints under balanced axial loading. The proposed parametric formulae agree well with the experimental data.
KW - Carbon fibre reinforced polymer
KW - CFRP strengthening
KW - Circular hollow section gap K-joint
KW - Finite element analysis
KW - Parametric formulae
KW - SCF reduction coefficient
UR - http://www.scopus.com/inward/record.url?scp=85079843046&partnerID=8YFLogxK
U2 - 10.1016/j.engstruct.2020.110369
DO - 10.1016/j.engstruct.2020.110369
M3 - Journal article
AN - SCOPUS:85079843046
SN - 0141-0296
VL - 210
JO - Engineering Structures
JF - Engineering Structures
M1 - 110369
ER -