# gst: modeling around the edge of a crack

<< It is said that a weak link determines the strength of the entire chain. Likewise, defects or small cracks in a solid material may ultimately determine the strength of that material – how well it will withstand various forces >>

<< What, exactly, happens right around the edge of the crack, in the area in which those large stresses are concentrated? >>

The Breaking Point. What happens at the moving edge of crack? Aug 23, 2017

https://wis-wander.weizmann.ac.il/chemistry/breaking-point

https://www.sciencedaily.com/releases/2017/08/170823094054.htm

AA << show that cracks undergo an oscillatory instability controlled by small-scale, near crack-tip, elastic nonlinearity. This instability occurs above an ultrahigh critical velocity and features an intrinsic wavelength proportional to the ratio of the fracture energy to the elastic modulus (..) This ratio emerges as a fundamental scaling length assumed to play no role in the classical theory of cracks, but shown here to strongly influence crack dynamics >>

Chih-Hung Chen, Eran Bouchbinder & Alain Karma. Instability in dynamic fracture and the failure of the classical theory of cracks. Nature Physics doi: 10.1038/nphys4237 Publ. Aug 21, 2017

https://www.nature.com/nphys/journal/vaop/ncurrent/full/nphys4237.html