On the Modeling of the Dynamic Crack Propagation by Extended Finite Element Method: Numerical Implementation in Dynela Code

The development of the computational techniques used in the analyzes of the dynamic fracture and their implementation in numerical codes takes a growing importance in last years. This interest derives from the necessity to predict the localisation of the initiations of cracks, when and in which direction this crack will propagate throw the material under dynamic loads. Several numerical approaches were proposed during few past decades in order to analyze discontinuous phenomena like cracks and shear bands occurring in structures under quasi-static or dynamic loads. In this paper we present the numerical implementation of the Extended Finite Element Method (XFEM), one of the latest approach developed in order to model the dynamic discontinuities. The crack representation in XFEM is based on the enrichment of the classical displacement-based finite element approximation through the framework of partition of unity method. In this approach, a crack is modeled introducing additional degrees of freedom to the nodes whose nodal shape function support intersects this one.The explicit dynamic FEM code DynELA developed in the LGP in Tarbes using an object-oriented framework is used to support the implementation of the XFEM as a new module called DynaCrack.