Failure Analysis of Composite Bonded Joints
Abstract
Because of the ineffectiveness of the commonly used failure criteria, current analysis methods fail to accurately predict the strength of bonded composite joints. This analytical shortfall results in overly conservative joint designs. In a composite bonded joint, failure typically occurs in the first ply of the parent laminate near the stress singularity. In this study, and average strain approach is used to analyze this area and the first strain invariant failure Criterion, also called the J, failure criterion, is adopted to predict the failure load of composite bonded joints. The analysis is based on a plane strain two-dimensional finite element model, which includes both the effects of geometric and material nonlinearity. The predicted failure loads correlate well with reported test results. Utilizing existing test data for composite bonded joints, it was found that the critical J values in the first ply of the parent laminates are almost constant. The merit of the J failure criterion is that it is valid for various environmental conditions, loading conditions, and surface ply orientations.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1999
- Accession Number
- ADA375743
Entities
People
- David Barrett
- Hsi C. Tsai
- James Alper
Organizations
- Naval Air Warfare Center