Phase field modeling of hydraulic fracturing with interfacial damage in highly heterogeneous fluid-saturated porous media

Abstract

International audienceIn this work, we propose an extension of the phase field model for the modeling of hydraulic fracturing or cracking in heterogeneous saturated porous media. The involved extensions comprise: (a) taking into account interfacial damage between the inclusions and the matrix; (b) modeling fluid flow within both matrix cracks and interfacial cracks; (c) the possibility to handle geometries of the heterogeneous media in the form of regular grids of voxels e.g. as obtained from experimental imaging techniques. The developed numerical framework is based on the phase field method with a regularized description of both bulk and interface discontinuities, extended to a fully coupled hydro-mechanical framework. Both 2D and 3D examples are presented for hydro-mechanical microcracking initiation and propagation in voxel-based models of complex heterogeneous media with interfacial damage between the inclusions and the matrix

Phase-field modeling of hydraulic fracture network propagation in poroelastic rocks

“…A linear increase of the fluid pressure is observed at the initial stage, for example when t < 0.9 s. After reaching the maximum value (around 6 × 10 5 Pa) at 1.2 s, the fluid pressure decreases gradually to the asymptotic value at around 4.5 × 10 5 Pa. The simulation results presented are in line with these in [31] which verifies the developed phase-field approach for modeling hydraulic fracturing.…”

“…Due to the deformation, the zone at front of the propagating crack tips (see also Fig. 14) may pose negative fluid pressure which has also been observed in former contribution [29,31]. The negative fluid pressure is also encountered at some natural fractures, for example, the fluid pressures at F1 and F9 drop down to negative values at the initial stage as shown in Fig.…”

“…where 1 is the identity 2-order matrix, n s ¼ ∇ s ∇ s k k is the normal vector defined by the phase field, and w = h ∇ u • n s is the fracture width representing the displacement jump with h being a length parameter (approximated by the mesh size in practice [19,40]). The normal displacement jump along the fracture interfaces can be expressed as w n = w • n s according to [31].…”

“…Phase-field models for hydraulic fracturing in saturated permeable porous media were then developed by Miehe et al [19], Lee et al [28], and Mikelic et al [29,30] based on Biot's equation of poroelasticity. Xia et al [31] and Shu et al [32] further considered the material heterogeneity and the dynamic effects in the phase-field model for hydraulic fracture in porous media. Santillan et al [33,34] proposed another framework for hydraulic fracture in both impermeable and permeable solids using phase-field approach with fluid flow in fracture being a lower-dimension manifold.…”

Modelling progressive failure in multi-phase materials using a phase field method

“…Nguyen et al [60] introduced a smoothed displacement jump approximation of the interface by restoring to the level set method in phase field model. The approach allows interactions between matrix cracking and interface debonding [61,62]. Msekh et al [63,64] applied the phase field approach to model progressive failure in polymer-matrix composites.…”