Peridynamic and cohesive zone model approachesfor crack propagation modelling

In different fields of human activities the structural components have to be in use, despite ageing and the continuous risk of damage growth and consequent possible failure. The capability to predict damage evolution by adequate numerical techniques is clearly extremely important, both for safety and economy reasons. Delamination in composite structures has been widely investigated from experimental and numerical point of view, because it can often cause local failures and, sometimes, of sudden structural collapses. In this paper two different numerical approaches will be presented to study crack propagation phenomena in structural materials: the first based on cohesive zone model techniques and the other based on the recently proposed peridynamic theory. The same methods can be used to study delamination damage in composite materials. Some examples of applications of the peridynamic method will be presented. A strategy used to increase the accuracy of the finite difference solution techniques will be applied also to an equivalent finite element model.