Finite Element Implementation of Advanced Failure Criteria For Composites

The need for high performance-to-weight ratio structures coming from the most advanced engineering fields is the main driver of the increasing usage of composite materials for critical applications. In order to design light and safe systems on time to meet the market requirements, accurate and effective analysis tools are necessary.

NASA has recently developed LaRC02, a set of first-ply-failure criteria for composites which have been shown to be accurate and physically consistent. The LaRC02 formulation seemed to be particularly well suited for design purposes, due to its optimal trade-off between accuracy, material characterization requirements, computational effort and ease of results interpretation.

The present work describes with some insights the LaRC02 criterion features and its implementation into NEiNastran, a commercial finite element software package. The accuracy and usefulness of the method are shown through some application examples, ranging from simple validation cases to a real-world structure.