Resistance Curve Approach to Predicting Residual Strength of Composites.
Abstract
This report describes an analysis method to predict the static strength of a composite laminate with a delamination, using the resistance curve approach. Experimental data available in the literature were analyzed to establish Mode I and Mode II resistance curves and the mixed mode interaction criterion. A procedure to determine the Mode II resistance curve from mixed mode test data was discussed. An experimental program was conducted to determine if composites exhibit resistance curve in Mode II. Two material systems were tested in the program. One of those systems was AS4/3501-6 which is representative of currently used graphite/epoxy materials. The second system was IM6/5245C which consists of an enhanced toughness matrix and high modulus, high strain to failure fibers. In addition, static compression tests were conducted on coupon specimens with through-the-width embedded delaminations to verify the analytical predictions. An analysis method was developed for residual strength prediction. The analysis is based on strain energy release rate approach. Strain energy release rate was computed at the delamination fron at applied compressive stress level above the initial buckling stress of the delamination. The residual strength was predicted using a multiple failure mode criteria.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1986
- Accession Number
- ADA176984
Entities
People
- C. Shah
- H. P. Kan
- R. B. Deo
- R. Kinslow