Theory and Verification of the Fiber Composite Damage Model Implemented in DYNA3D
Abstract
A laminated shell formulation and damage model for fiber-composite materials are implemented in DYNA3D, a three-dimensional finite element code to analyze the large deflection and materially nonlinear response of structures and solids. The damage model consists of an interactive failure criterion and a post-failure degradation rule. The failure criterion identifies three modes of failure: matrix cracking, matrix compression failure, and fiber breakage. When a failure criterion is met, some of all of the lamina's elastic constants are set to zero. The failure and model and post-failure degradation rule are compared with experimental results available from the literature to establish the validity of the damage model. Comparisons between the failure criteria and experimental results indicate that the Chang fiber breakage criterion is an agreement with biaxial stress test data is reasonable assumptions are made regarding matrix cracking prior to fiber breakage. However, the matrix failure criteria do not adequately model matrix strength under combined loading conditions. A modified form of the Tsai-Wu criterion is in better agreement with the test data and is recommended for implementation into DYNA3D. A flexible post-failure degradation rule is also recommended: modifications to the current implementation are suggested which allow the user to specify the degradation behavior for each mode of failure.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1989
- Accession Number
- ADA216600
Entities
People
- Yvonne D. Murray