Surface Deformation of Brittle Materials.

The Breaking of Brittle Materials

A long metal thread breaks more easily than a short one—an observation Leonardo da Vinci made in the 15th century. It all comes down to simple statistics: the larger an object, the more likely it is to contain a region that breaks when subject to stress. The fracture properties of brittle materials also depend on the disorder in their underlying structure: a homogeneous material like glass brea...

Brittle Deformation of Solid and Granular Materials with Applications to Mechanics of Earthquakes and Faults

Crack initiation in brittle materials

In this paper we study the crack initiation in a hyper-elastic body governed by a Griffith’s type energy. We prove that, during a load process through a time dependent boundary datum of the type t → tg(x) and in absence of strong singularities (this is the case of homogeneous isotropic materials) the crack initiation is brutal, i.e., a big crack appears after a positive time ti > 0. On the cont...

Creep: Time‐dependent brittle deformation in rocks

4 Effective toughness of heterogeneous brittle materials

A heterogeneous brittle material characterized by a random field of local toughness K c (x) can be represented by an equivalent homogeneous medium of toughness, K eff. Homogenization refers to a process of estimating K eff from the local field K c (x). An approach based on a perturbative expansion of the stress intensity factor along a rough crack front shows the occurrence of different regimes...