Accession Number : AD0760361

Title :   Fracture Analysis of Undirectional and Angle-Ply Composites.

Descriptive Note : Final rept. May-Dec 72,

Corporate Author : LEHIGH UNIV BETHLEHEM PA INST OF FRACTURE AND SOLID MECHANICS

Personal Author(s) : Sih,G. C. ; Chen,E. P.

Report Date : JAN 1973

Pagination or Media Count : 61

Abstract : The concept of fracture mechanics is applied to analyze the brittle fracture of unidirectional and angle-ply composites. The analytical prediction based on the newly developed energy density theory agrees well with the experimental data on Scotchply 1002 where crack propagation occurs along the fiber direction. The energy density theory represents a departure from the classical stress-intensity factor concept in that it is designed to treat the mixed mode fracture problem. A model for analyzing the delamination problem is also proposed in which a core region is assigned to the location of possible failure. The radius of this region is estimated from an approximate stress solution of a balanced four-layered laminate. Existing experimental data are not adequate for making a meaningful comparison with the analytical results. (Author, modified-PL)

Descriptors :   (*COMPOSITE MATERIALS, *FRACTURE(MECHANICS)), CRACKS, CRACK PROPAGATION, RHEOLOGY, FAILURE(MECHANICS), REINFORCED PLASTICS, FIBERS, LAMINATES, MATHEMATICAL MODELS

Subject Categories : Laminates and Composite Materials

Distribution Statement : APPROVED FOR PUBLIC RELEASE