Computational non-smooth fracture dynamics in non linear and heterogeneous materials. Application to fracture of hydrided zircaloy

This paper presents a new computational method and the associated software dedicated to the study of the dynamic fracture of nonlinear and heterogeneous materials. This method is based on the concept of Frictional Cohesive Zone Model in the framework of Non-Smooth Contact Dynamics. The associated numerical platform, composed of three object-oriented libraries, allows to simulate, in three dimensional finite deformations, the dynamic fracture of both multiphase and functionally graded materials from crack initiation to post-fracture behavior. The ability of this software, developed by the French 'Institut de Radioprotection et de Surete Nucleaire' (IRSN) in the frame of its research program on nuclear fuel safety, is illustrated on the fracture of hydrided Zircaloy-4, constituting nuclear cladding tubes at high burnup, during a reactivity initiated accident (RIA). The macroscopic behavior of this heterogeneous material is deduced as an averaged energy release rate depending on the volume fraction of hydride phase. (authors)