ABAQUS user-element subroutine (UEL) with a robust phase field formulation for fracture. Several integration schemes are available, as detailed in the accompanying documentation.
Paper: E. Martínez-Pañeda, A. Golahmar, C.F. Niordson. A phase field formulation for hydrogen assisted cracking. Computer Methods in Applied Mechanics and Engineering, 342: 742-761 (2018)
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