TY - JOUR
T1 - Effect of delamination on the fatigue life of GFRP
T2 - A thermographic and numerical study
AU - Colombo, Chiara
AU - Bhujangrao, Trunal
AU - Libonati, Flavia
AU - Vergani, Laura
N1 - Publisher Copyright:
© 2019
PY - 2019/6/15
Y1 - 2019/6/15
N2 - Delamination is the major failure mechanism in composite laminates and eventually leads to material failure. An early-detection and a better understanding of this phenomenon, through non-destructive assessment, can provide a proper in situ repair and allow a better evaluation of its effects on residual strength of lightweight structural components. Here we adopt a joint numerical-experimental approach to study the effect of delamination on the fatigue life of glass/epoxy composites. To identify and monitor the evolution of the delamination during loading, we carried out stepwise cyclic tests coupled with IR-thermography on both undamaged and artificially-damaged samples. The outcome of the tests shows that IR-thermography is able to identify a threshold stress, named damage stress σ D , which is correlated to the damage initiation and the fatigue performance of the composite. Additionally, we performed FE-simulations, implementing the delamination by cohesive elements. Such models, calibrated on the basis of the experimental fatigue results, can provide a tool to assess the effect of parameters, such as the delamination size and location and composite stacking sequence, on the residual strength and fatigue life of the composite material.
AB - Delamination is the major failure mechanism in composite laminates and eventually leads to material failure. An early-detection and a better understanding of this phenomenon, through non-destructive assessment, can provide a proper in situ repair and allow a better evaluation of its effects on residual strength of lightweight structural components. Here we adopt a joint numerical-experimental approach to study the effect of delamination on the fatigue life of glass/epoxy composites. To identify and monitor the evolution of the delamination during loading, we carried out stepwise cyclic tests coupled with IR-thermography on both undamaged and artificially-damaged samples. The outcome of the tests shows that IR-thermography is able to identify a threshold stress, named damage stress σ D , which is correlated to the damage initiation and the fatigue performance of the composite. Additionally, we performed FE-simulations, implementing the delamination by cohesive elements. Such models, calibrated on the basis of the experimental fatigue results, can provide a tool to assess the effect of parameters, such as the delamination size and location and composite stacking sequence, on the residual strength and fatigue life of the composite material.
KW - Cohesive elements
KW - Delamination
KW - GFRP-composites
KW - IR-thermography
UR - https://www.scopus.com/pages/publications/85063109994
U2 - 10.1016/j.compstruct.2019.03.023
DO - 10.1016/j.compstruct.2019.03.023
M3 - Article
AN - SCOPUS:85063109994
SN - 0263-8223
VL - 218
SP - 152
EP - 161
JO - Composite Structures
JF - Composite Structures
ER -