Abstract

Quasibrittle materials are materials in which the fracture process zone (FPZ) is not negligible as compared with the cross section dimension and encompass a wide variety of materials such as concrete, mortar, rocks, toughened ceramics, frozen sand, and ice also belongs to this class of materials. The size of the FPZ is typically 5-50 times the size of the dominant material inhomogeneity and for ice, it could be the grain size. For type 1 size effect which occurs in positive geometry structures failing at macrocrack initiation and is typical of flexural failures, the size effect is governed by Weibull statistics when the structure size dwarfs the size of the FPZ . When the structure size is comparable to the size of the FPZ , the probability distribution of the quasibrittle fracture can be described by a Gaussian core with a far-left Weibull tail. This is concluded from scaling laws derived from a hierarchical model of chains and bundles of representative volume elements starti ng from the atomic scale and include the effects of loading rate and temperature. The implications of probabilistic fracture mechanics on the strength of ice are investigated for different size of the ice sheet, varying strain rates and temperature effect.