Statistical strength models for composites with discontinuities

Miscellaneous · Tue Jan 01 00:00:00 EST 1991

OSTI ID:6906078

Cheng, Ming-Chih

This thesis investigates the microfracture process in laminated composites based on a problematic approach. Two probabilistic fracture models, a statistical model and a stochastic model, were developed for predicting the failure stress in composites containing geometric discontinuities such as holes and cracks. A two-parameter Weibull distribution of fiber strength and the elastic properties of matrix materials are used in the analysis. The results show that the fracture stress is related to notch size by a power law similar to that proposed by Mar and Lin. Experiments were conducted to verify the probabilistic fracture models developed. The strength reduction factors for boron/epoxy (0/-45/0/45)s laminates were obtained and the fiber damage near the hole edge was studied. The experimental data agree well with the predictions from the probabilistic fracture models.

• Research Organization: Washington Univ., Seattle, WA (United States)
• OSTI ID: 6906078
• Resource Relation: Other Information: Thesis (Ph.D.)
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BORON
FRACTURE PROPERTIES
COMPOSITE MATERIALS
MATHEMATICAL MODELS
EPOXIDES
CRACKS
DAMAGE
ELASTICITY
FAILURES
FIBERS
MATRIX MATERIALS
NOTCHES
STATISTICS
STOCHASTIC PROCESSES
ELEMENTS
MATERIALS
MATHEMATICS
MECHANICAL PROPERTIES
ORGANIC COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
SEMIMETALS
TENSILE PROPERTIES
360603* - Materials- Properties