Experimental research on fracture behaviors of damaged CFRP tendons: Fracture mode and failure analysis

In this paper, the fracture toughness associated with longitudinal tensile failure and the fracture energy associated with transverse compression failure of T700/CP-02A/B carbon -epoxy unidirectional composites are measured from different tests. For this type of composite, the critical energy release rate based on linear elastic fracture mechanics (LEFM) and the fracture energy based on digital image correlation (DIC) techniques were calculated to investigate the validity of the concept of fracture energy. The results of the transverse compression test showed that damage appeared in the composites when the loading work reached the fracture energy value of 9.63 kJ/m2. Based on the results of the fracture toughness test, carbon fiber reinforced polymer (CFRP) tendons with the same material and craftsmanship were used to investigate the fracture behavior after damage appeared due to the anchorage pressure. The experimental results showed that longitudinal cracking would occur in the damaged CFRP tendons under longitudinal tension and ultimately lead to splitting failure. The applied prestress for CFRP tendons is sufficient to cause splitting failure of damaged CFRP tendons in a prestressed structure. (C) 2016 Elsevier Ltd. All rights reserved.