Numerical modelling in non linear fracture mechanics

Abstract

Some numerical studies of crack propagation are based on using constitutive models that account

for damage evolution in the material. When a critical damage value has been reached in a material

point, it is natural to assume that this point has no more carrying capacity, as is done numerically in the element

vanish technique. In the present review this procedure is illustrated for micromechanically based material

models, such as a ductile failure model that accounts for the nucleation and growth of voids to coalescence,

and a model for intergranular creep failure with diffusive growth of grain boundary cavities leading

to micro-crack formation. The procedure is also illustrated for low cycle fatigue, based on continuum damage

mechanics. In addition, the possibility of crack growth predictions for elastic-plastic solids using cohesive

zone models to represent the fracture process is discussed.