Fiber breakage due to shear constraint effect in plain woven glass fabric composites under tension/shear biaxial cyclic loading

摘要

Fiber breakage in fiber bundles of a plain woven glass fabric composites was evaluated under tension/shear biaxial cyclic loading. Remarkable effect of biaxial stress ratio on the fiber breakage and its accumulation was found. Under pure tension (uniaxial) cyclic loading, the variation of fiber breakage ratio with respect to loading cycles was divided into two stages in the longitudinal fiber bundles. In the first stage, the fiber breakage scarcely occurred. Fibers in a fiber bundle were broken remarkably in the final stage. Under the biaxial cyclic stress containing shear stress component, the fiber breakages in the longitudinal fiber bundle were also observed in the initial fatigue stage. The characteristics of fiber breakage under biaxial loading were explained by the producing and releasing of the shear constraint effect. The broken fibers were actually observed at the predicted point by the shear constraint effect model.