Evaluation of the effect of fiber bridging on mode I quasi‐static testing

Abstract

AbstractThe purpose of this investigation is to evaluate the contribution of fiber bridging to the energy release rate of a fracture resistance curve. Fiber bridging occurs when testing beam‐type specimens consisting of unidirectional plies in a laminate. Unidirectional double cantilever beam specimens composed of the carbon fiber reinforced polymer prepreg AS4/8552 were tested using standard methods. In addition, a cohesive zone model was developed and used to carry out finite element analyses on the tested specimens. It was employed to calculate the contribution of fiber bridging to the ‐curve which was determined from the tests. Fiber bridging in beam specimens increases the apparent fracture toughness of a composite laminate. A method has been proposed for evaluating its contribution to the energy release rate. In that way, an ‐curve may be determined for which the effect of fiber bridging is eliminated.