Cracks faster than the shear wave speed
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 2 times the material shear wave speed. These observations have similarities to shallow earthquake events where intersonic shear rupture speeds have been surmised.
Rosakis
AJ
Graduate Aeronautical Laboratories, California Institute of Technology, Pasadena, CA 91125, USA.
Samudrala
O
Coker
D