Benchmark test for mode I fatigue-driven delamination in GFRP composite laminates: Experimental results and simulation with the inter-laminar damage model implemented in SAMCEF

Abstract

Adopting effective and accurate numerical tools capable of predicting damage effects on the structure reduces design, certification, and maintenance costs. However, the tools to assess progressive delamination under high-cycle fatigue are rarely validated against realistic benchmark tests different from simple tests on coupon specimens that can be simplified to a 2D geometry. This work presents a benchmark test on a demonstrator specimen made of a non-crimp fabric laminated Glass Fiber Reinforced Polymer (GFRP) used in the wind energy industry. The case shows varying crack growth rates and crack front shape over the fatigue life, making it more representative of structures in service than coupon specimens. Moreover, the test is simulated with the first commercially available tool to assess progressive delamination under high-cycle fatigue loading based on a cohesive zone model approach. The method is implemented in the Simcenter Samcef 2021.2 software package dedicated to mechanical virtual prototyping. A characterization testing campaign on coupon specimens is carried out to obtain the material properties for the method. The numerical method can reproduce the experimental results on the demonstrator specimen regarding crack front shape evolution and crack front location versus the number of fatigue cycles