TY - JOUR
T1 - Fatigue tests and design of CFRP-strengthened CHS gap K-joints
AU - Tong, Lewei
AU - Xu, Guowen
AU - Zhao, Xiao Ling
AU - Yan, Yang
N1 - Funding Information:
The authors are grateful for the financial support from the National Key R&D Program of China (No. 2019YFB1600702 ), Shanghai Civil Engineering Peak Discipline Program of Shanghai Municipal Education Commission, China (No. 2019010301 ) and China Railway Shanghai Design Institute Group Research, China Project (No. 20-63 ).
Publisher Copyright:
© 2021 Elsevier Ltd
PY - 2021/6
Y1 - 2021/6
N2 - This paper presents an experimental study on the fatigue behaviour of circular hollow section (CHS) gap K-joints strengthened by carbon fibre-reinforced polymer (CFRP) sheets (CFRP-CHS K-joint). Eight CFRP-CHS K-joints and three reference un-strengthened CHS gap K-joints were tested under cyclic axial loading. Fatigue failure modes of the CFRP-strengthened and un-strengthened joints were determined and compared. Fatigue lives in three fatigue failure criteria were recorded: crack-initiation fatigue N2, through-thickness fatigue N3, and end-of-test fatigue N4. The comparisons indicate that CFRP-CHS K-joints have a longer fatigue life than un-strengthened joints in the same nominal stress range, regardless of fatigue failure criteria (N2, N3, or N4). The increase in N3 was approximately 138%, on average. No significant difference in fatigue data in terms of hot spot stress range was found between the CFRP-strengthened and un-strengthened joints. Based on the experimental fatigue data, a modified Sr,hs-N curve based on the CIDECT recommended curve was proposed for CFRP-CHS K-joints.
AB - This paper presents an experimental study on the fatigue behaviour of circular hollow section (CHS) gap K-joints strengthened by carbon fibre-reinforced polymer (CFRP) sheets (CFRP-CHS K-joint). Eight CFRP-CHS K-joints and three reference un-strengthened CHS gap K-joints were tested under cyclic axial loading. Fatigue failure modes of the CFRP-strengthened and un-strengthened joints were determined and compared. Fatigue lives in three fatigue failure criteria were recorded: crack-initiation fatigue N2, through-thickness fatigue N3, and end-of-test fatigue N4. The comparisons indicate that CFRP-CHS K-joints have a longer fatigue life than un-strengthened joints in the same nominal stress range, regardless of fatigue failure criteria (N2, N3, or N4). The increase in N3 was approximately 138%, on average. No significant difference in fatigue data in terms of hot spot stress range was found between the CFRP-strengthened and un-strengthened joints. Based on the experimental fatigue data, a modified Sr,hs-N curve based on the CIDECT recommended curve was proposed for CFRP-CHS K-joints.
KW - Carbon fibre-reinforced polymer
KW - CFRP strengthening
KW - Circular hollow section gap K-joint
KW - Fatigue test
KW - S–N curve
UR - http://www.scopus.com/inward/record.url?scp=85103978358&partnerID=8YFLogxK
U2 - 10.1016/j.tws.2021.107694
DO - 10.1016/j.tws.2021.107694
M3 - Journal article
AN - SCOPUS:85103978358
SN - 0263-8231
VL - 163
JO - Thin-Walled Structures
JF - Thin-Walled Structures
M1 - 107694
ER -