A Review on fracture-mechanics based models on debonding nature of CFRP/Concrete composites

Abstract

Debonding failure of externally strengthened CFRP/concrete composites is the most critical failure mode which needs to prevent to achieve a beneficial strengthening solution. Many theoretical and numerical models have been developed to predict the failure load of CFRP/concrete composites. Existing theoretical models are grounded on strength-based and fracture-mechanics based approaches. The use of strength-based models is obsolete due to their inability to estimate the failure behaviour throughout the debonding process. By means of fracture-mechanics based models, both the initiation and propagation of cracks can be explored in terms of interface fracture energy. In the present study, existing fracture-mechanics based models are evaluated using a database and the reliability of the models are analyzed using statistical parameters and suggests best models which can accurately quantify the debonding failure load of CFRP/concrete composites. In addition, a new reduction factor aGF is introduced for interfacial fracture energy for the debonding failure mode which takes place along the CFRP/concrete interface.