Cracks faster than the shear wave speed

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1999-05-21
Rosakis, A.J.
Samudrala, O.
Çöker, Demirkan
Classical dynamic fracture theories predict the surface wave speed to be the limiting speed for propagation of in-plane cracks in homogeneous, Linear elastic materials subjected to remote Loading. This report presents experimental evidence to the contrary. Intersonic shear-dominated crack growth featuring shear shock waves was observed along weak planes in a brittle polyester resin under far-field asymmetric loading. When steady-state conditions were attained, the shear cracks propagated at speeds close to root 2 times the material shear wave speed. These observations have similarities to shallow earthquake events where intersonic shear rupture speeds have been surmised.

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Citation Formats
A. J. Rosakis, O. Samudrala, and D. Çöker, “Cracks faster than the shear wave speed,” Science, pp. 1337–1340, 1999, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/49249.