Pattern formation and selection in quasistatic fracture

Fracture in quasistatically driven systems is studied by means of a discret e spring-block model. Developed from close comparison with desiccation expe riments, it describes crack formation induced by friction on a substrate. T he model produces cellular, hierarchical patterns of cracks, characterized by a mean fragment size linear in the layer thickness, in agreement with ex periments. The selection of a stationary fragment size is explained by expl oiting the correlations prior to cracking. A scaling behavior associated wi th the thickness and substrate coupling, derived and confirmed by simulatio ns, suggests why patterns have similar morphology despite their disparity i n scales.