Structural Safety & Reliability Edited by

and ice. are materials that fail by fracture with a large fracture process zone. They have a heteroge-neous random microstructure. which causes significant scatter in material strength. The classical statistical strength models of Weibull-type, as well as some recent random process models for crack growth, are not applicable because they ignore the stress redistributions and energy release caused by large stable crack growth before failure, and the variability of critical energy release rate (the R-curve). This paper presents, in the first part. a new random process model for crack growth which takes the R-curve into account. The second part focuses on another related problem- the Weibull-type model. It reviews a recent nonlocal generalization of Weibull theory which can take into account the existence of a large fracture process zone and stable crack growth prior to maximum load