Virtual characterization of nonlocal continuum damage model parameters using a high fidelity finite element model

A virtual finite element framework is presented to provide the transition from a high fidelity model to a more computationally efficient continuum model for simulating fibre-dominated damage behavior in composite laminates subjected to tensile loadings. The high fidelity method in LS-DYNA is based on the use of cohesive interface elements to simulate both intra-laminar matrix cracks and delamination. Applied to IM7/8552 carbon fibre reinforced plastic laminates in over-height compact tension (OCT) tests, this modeling strategy is used to determine the effective damage parameters for the nonlocal continuum damage model, CODAM2, implemented as MAT219 in LS-DYNA. The prediction of CODAM2 is thoroughly assessed against quantitative and qualitative results obtained from the high fidelity model. Furthermore, the characterized CODAM2 model is applied to simulations of large-scale OCT, open-hole tension (OHT) and center-notched tension (CNT) specimens and results are compared to corresponding experimental data. Due to its nonlocal feature to track the crack trajectory without the need to align the mesh with fibre orientation, the continuum damage model CODAM2 is able to accurately predict the structural response in all large-scale OCT, OHT and CNT test cases with significant computational efficiency.

Automated summary

A virtual finite element framework is proposed to simulate fiber-dominated damage behavior in composite laminates under tensile loading, transitioning from high fidelity to computationally efficient models. The effectiveness of the nonlocal continuum damage model CODAM2 in predicting structural response in large-scale tests is demonstrated through comparison with high fidelity models and experimental data.