The suitability of traditional fatigue design methods to deal with complex damage modes in composite materials is critically assessed. After a survey of the recent fatigue models, a new methodology is developed, based on both the Markovian discrete time discrete state stochastic processes and the Critical Element Model for damage in composite materials. In a practical application of the methodology, the fatigue behavior of cross ply Carbon Epoxy laminates is derived from a Monte-Carlo simulation. |