TY - JOUR
T1 - The bond behaviour of CFRP-to-concrete bonded joints under fatigue cyclic loading
T2 - An experimental study
AU - Zhou, Hao
AU - Fernando, Dilum
AU - Thuan Nguyen, Van
AU - Dai, Jian Guo
N1 - Funding Information:
Authors would like to thank technicians at the UQ structures lab for their help in carrying out experimental tests. The authors are also grateful for the financial support received from the Australian Research Council under the Linkage Project funding scheme to the second author (LP150101033).
Publisher Copyright:
© 2020 Elsevier Ltd
Copyright:
Copyright 2020 Elsevier B.V., All rights reserved.
PY - 2020
Y1 - 2020
N2 - Carbon fibre reinforced polymer (CFRP) has been accepted by the construction industry as an excellent material for strengthening reinforced concrete (RC) structures against flexural and shear loads. Behaviour of such CFRP strengthened RC structures under quasi-static loading conditions is well understood. Most of the existing studies on CFRP strengthened RC structures under fatigue cyclic loading are focused on demonstrating the effectiveness of the CFRP strengthening on enhancing the fatigue life. However, bond-slip behaviour, a key behaviour governing the performance of flexural/shear strengthened RC structures using externally bonded CFRP, under fatigue cyclic loading remain largely unknown. This paper presents an experimental study aimed at investigating the behaviour of CFRP-to-concrete bonded joints under fatigue cyclic loading. A novel data acquisition system was developed to obtain the strain distribution along the bond length at required force intervals. Experimental results revealed that CFRP-to-concrete bonded joints under fatigue cyclic loading could fail in many different failure modes including, cohesion failure within concrete, cohesion failure within adhesive, and interlaminar failure within CFRP laminate. Failure mode was found to be dependent on the strength of concrete, type of the CFRP laminate, and loading amplitude. Bond-slip relations under fatigue cyclic loading showed that the fatigue damage initiates when the interfacial shear stress is above 80% of the interfacial shear strength.
AB - Carbon fibre reinforced polymer (CFRP) has been accepted by the construction industry as an excellent material for strengthening reinforced concrete (RC) structures against flexural and shear loads. Behaviour of such CFRP strengthened RC structures under quasi-static loading conditions is well understood. Most of the existing studies on CFRP strengthened RC structures under fatigue cyclic loading are focused on demonstrating the effectiveness of the CFRP strengthening on enhancing the fatigue life. However, bond-slip behaviour, a key behaviour governing the performance of flexural/shear strengthened RC structures using externally bonded CFRP, under fatigue cyclic loading remain largely unknown. This paper presents an experimental study aimed at investigating the behaviour of CFRP-to-concrete bonded joints under fatigue cyclic loading. A novel data acquisition system was developed to obtain the strain distribution along the bond length at required force intervals. Experimental results revealed that CFRP-to-concrete bonded joints under fatigue cyclic loading could fail in many different failure modes including, cohesion failure within concrete, cohesion failure within adhesive, and interlaminar failure within CFRP laminate. Failure mode was found to be dependent on the strength of concrete, type of the CFRP laminate, and loading amplitude. Bond-slip relations under fatigue cyclic loading showed that the fatigue damage initiates when the interfacial shear stress is above 80% of the interfacial shear strength.
KW - Bond-slip behaviour
KW - Debonding
KW - Fatigue cyclic loading
KW - FRP-to-concrete
UR - http://www.scopus.com/inward/record.url?scp=85097084162&partnerID=8YFLogxK
U2 - 10.1016/j.conbuildmat.2020.121674
DO - 10.1016/j.conbuildmat.2020.121674
M3 - Journal article
AN - SCOPUS:85097084162
SN - 0950-0618
JO - Construction and Building Materials
JF - Construction and Building Materials
M1 - 121674
ER -