Concepts for bridged Mode ii delamination cracks

Limiting cases and length scales are detailed for Mode II delamination cracks bridged by through-thickness reinforcement. Analytical results are found for two limits: a steady-state configuration indicative of noncatastrophic failure and a small-scale bridging configuration indicative of catastrophic failure. General large-scale bridging conditions are studied numerically using bending theory for anisotropic plates. The effects of the mechanical properties of the laminate and the reinforcement, notch length, and plate thickness on the transition between the two limiting configurations, notch sensitivity and mechanical behavior are analyzed. All of these effects can be expressed succinctly in terms of a few length scales which are material-structure parameters involving the plate thickness.

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