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arXiv · 1607.01137

Crack front instabilities under mixed mode loading in three dimensions

Hervé Henry
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Abstract

The evolution of a crack front under mixed mode loading (I+III) is studied using a phase field model in 3 dimensions with no stress boundary conditions. As previously observed experimentally in gels, there is a relaxation toward a geometry where $K_{III}=0$ without any front fragmentation even for high values of the initial mode mixity $K_{III}/K_{I}$. The effects of the initial condition is studied and it is shown that irregularities in the initial slit can lead to front fragmentation for smaller values of the ratio $K_{III}/K_{I}$ as is observed in experiments.

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Hervé Henry. 2016-07-05. Crack front instabilities under mixed mode loading in three dimensions. https://doi.org/10.1209/0295-5075/114/66001

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