Alexander Chudnovsky, achudnov@uic.edu
Scale Effect in Brittle Fracture
Heterogeneous morphology and a hierarchy of defects from grain size level up to a large-scale network of
cracks are typical for most of engineering materials. It create a challenge for determining macroscopic properties of materials, particularly the scale dependent ones such as strength, toughness and other brittle fracture
characteristics. The most pictorial manifestation of material heterogeneity are highly irregular and random
fracture surfaces. Modeling of brittle fracture of micro-heterogeneous materials calls for a synthesis of fracture
mechanics with probability and stochastic calculus. This work present a brief overview of Statistical Fracture
Mechanics that addresses the statistical aspects of fracture. It is illustrated by studies of concrete brittle fracture
and includes determination of a scaling rule for fracture toughness. Complex interaction between a macroscopic
crack and an array of pre-existing micro-defects results in highly tortuous, stochastic fracture paths and in large
scatter of all fracture-related parameters. Results of application of Statistical Fracture mechanics and related
experimental studies are reported in this presentation.