Probabilistic modelling of safe crack growth and estimation of the durability of structures

Probabilistic models of crack growth are considered at the macro-level of material deformation. These probabilistic models have parameters that can be determined from a fracture mechanics approach. Results from statistical analyses of defects in welded joints show that it is possible to use a two-parameter Weibull distribution as a basic model for the distribution of defect size. On the basis of a Monte Carlo numerical simulation of crack growth, one can construct complete probabilistic diagrams for structural integrity. These diagrams are the basis for designing structures containing defects.