Cumulative Fatigue Damage of Composite Laminates: Engineering Rule and Life Prediction Aspect

The analysis of cumulative fatigue damage is an important factor in predicting the life of composite elements and structures that are exposed to field load histories. A method for predicting the fatigue life of composite laminates under varying loads is suggested in this paper. A new theory of cumulative fatigue damage is introduced grounded on the Continuum Damage Mechanics approach that links the damage rate to cyclic loading through the damage function. A new damage function is examined with respect to hyperbolic isodamage curves and remaining life characteristics. The nonlinear damage accumulation rule that is presented in this study utilizes only one material property and overcomes the limitations of other rules while maintaining implementation simplicity. The benefits of the proposed model and its correlation with other relevant techniques are demonstrated, and a broad range of independent fatigue data from the literature is used for comparison to investigate its performance and validate its reliability.

Automated summary

This paper suggests a method to predict the fatigue life of composite laminates under varying loads. It introduces a new theory of cumulative fatigue damage based on Continuum Damage Mechanics, where the damage rate is linked to cyclic loading through the damage function. The proposed model is demonstrated to have benefits and reliability through comparison with other techniques and validation with independent fatigue data.