Modeling fatigue damage evolution in polymer matrix composite structures and validation using in-situ digital image correlation

摘要

A study is conducted with the aim of developing and implementing a fatigue prediction model for assessing the damage tolerance capabilities of polymer matrix composite structures. The damage mechanics based model uses empirical material parameters to represent orthotropic damage evolution. The model accounts for local multiaxial stresses as well as variable amplitude cyclic loading, which may result from local stress redistributions caused by damage evolution. The numerical results show the capability of the developed model to predict the variation of damage evolution and material property degradation in a tri-axially braided carbon fiber polymer matrix component. The predictions are validated by independent experiments on composite components using digital image correlation, which shows a strong correlation between the measured and predicted strain contours at various cyclic intervals. This is a key contribution and a step forward in developing a viable design tool for assessing the integrity and durability of composite structures. (C) 2015 Elsevier Ltd. All rights reserved.