Verification/prediction by numerical simulation of the resistance of large-scale metal and alloy structures subjected to extreme loads (e.g. accidental mechanical overload) that can lead to failure is a major issue in the transport, energy and defense sectors. This work presents a three-dimensional numerical methodology (i) capable of macroscopically accounting for the various dissipative mechanisms (plasticity, micro-voiding induced ductile damage) until failure, (ii) formulated within the framework of large deformation, (iii) implemented in a commercial computation code, and (iv) mesh-objective. The commercial computational code is ABAQUS-std, and the methodology is implemented as a user finite element (UEL). Geometric non-linearities are treated through an updated Lagrangian formulation (ULF) [1]. The more or less diffuse damage phase is described by the Gurson-Tvergaard-Needleman (GTN) microporous plasticity model [2] with standard finite elements method (FEM). The micro-void coalescence phase-induced dilation/shear band is described using an original extended cohesive finite element approach (XFEM-CZM) [3]. Progressive loss of cohesion leads to ultimate cracking, which is treated with extended finite elements method (XFEM). Particular attention is paid to transition criteria (damage to localization, localization to cracking), to the orientation of the localization plane (especially in Mode II), to the cohesive zone model (empirical vs. inspired by the micromechanics of micro-void coalescence), and to techniques for overcoming numerical issues (volumetric locking [4], numerical integration [5]). The unified methodology is capable of reproducing the degradation mechanisms and the fracture surface in large elastoplastic deformation of structures typical of laboratory tests, even for fairly coarse meshes. see Attached file for references