Fatigue damage modeling in laminated composite by using Rx-FEM and strength tracking method

The durability and residual load carrying capacity of composite materials is of critical importance for increasing their applicability. Regularized eXtended Finite Element Method framework for discrete modeling of damage evolution and interaction in laminated composites has been extended to increase the limit of crack density for a given mesh size. The formulation allows multiple twining of original nodes while the displacement discontinuity is represented by a pair of element twins maintaining the Gauss integration schema of the original element. Residual Strength Tracking methodology was applied for mesh independent crack insertion as well as in the initiation phase of the fatigue Cohesive Zone Model (CZM). An automatic cycle jump step selection algorithm within implicit framework was implemented to provide solution stability. The predictions were compared with the experimental data for three different open hole composite laminates under tension-tension fatigue and showed excellent agreement.

Automated summary

This study applies the regularized eXtended Finite Element Method (XFEM) framework to the discrete modeling of damage evolution and interaction in laminated composites. The crack density limit is increased for a given mesh size. The study also introduces the Residual Strength Tracking methodology and an automatic cycle jump step selection algorithm. The predictions show excellent agreement with experimental data.