Computational modeling of failure in composites under fatigue loading conditions

Applied Mechanic

Modeling fatigue-driving delamination using a thick level set interface model

This paper presents a new discontinuous damage model for simulating fatigue-driven delamination in composites. Fatigue models commonly describe crack growth using the Paris law which provides the link between the energy released due to delamination and the crack growth rate. A core issue in implementing the Paris law is to accurately compute the energy release rate. In common cohesive fatigue models the energy release rate is extracted locally from the cohesive law where improving the accuracy of computed energy release rate needs extra treatments. The new fatigue model proposed in this paper provides an accurate non-local method for extracting the energy release rate based on the thick level set approach. This model also profits from the kinematic capabilities of interface elements for modeling discontinuities along the interface. The model is validated by comparing the model predictions under dierent fracture modes with theoretical and experimental data which shows good agreement in all cases.Applied Mechanic

A thick level set interface model for simulating fatigue-drive delamination in composites

This paper presents a new damage model for simulating fatigue-driven delamination in composite laminates. This model is developed based on the Thick Level Set approach (TLS) and provides a favorable link between damage mechanics and fracture mechanics through the non-local evaluation of the energy release rate. Previously, this approach has been applied in the context of quasi-static continuum damage models. In this work, the thick level set method is translated to an interface model. The new interface damage model can be applied to quasistatic and fatigue simulations. It benefits from the kinematic flexibility of interface elements and preferable use of fracture mechanics for fatigue analysis. A 3D model is developed based on this approach and the obtained numerical results are validated with analytical and experimental data.Structural EngineeringCivil Engineering and Geoscience