Failure of a fiber composite lamina under three-dimensional stresses

摘要

The efficient use of thick-section fiber composites requires a proven three-211u001edimensional failure model. Numerous failure criteria have been proposed, but the 211u001elack of critical experimental results makes it difficult to assess the accuracy 211u001eof these models. It is shown that the various predictions for failure of a lamina 211u001edue to the simple state of uniaxial stress plus superposed hydrostatic pressure 211u001eare disparate. These differences are sufficient to allow evaluation of failure 211u001ecriteria using data that has the normal scatter found for composite materials. A 211u001ehigh-pressure test system for fiber composites is described and results for the 211u001eeffects of pressure on the transverse and longitudinal compression strengths of a 211u001ecarbon fiber/epoxy lamina are discussed. Results are compared with a few 211u001erepresentative failure models.