: In this work, we report on a successful benchmark program motivated by the development of robust hydro-mechanical coupled models capable of providing accurate equivalent properties, such as permeability and porosity, in larger computational cells, typical of an outcrop scale. The cells are occupied by a poroelastic fractured carbonate rock. Different research groups were invited to propose models and discretizations for the benchmark problem considering some basic premises. The construction of fine-scale models revolves around the non-linear elastic constitutive law postulated by Barton and Bandis between normal stress and normal displacement behavior. The local non-linear coupled poroelastic (matrix) - nonlinear elastic (joints) - flow (single phase) problem is solved under oedometric conditions considering a single realization of fractures locations generated through geostatistical analysis. The different research groups used a variety of techniques to solve the complex fine-scale problem. Among these techniques we may highlight embedded fracture elements , solid finite elements with high aspect ratio , augmented Lagrangian formulation [3, 4], local refinement with jump components  and zero thickness interface elements . Numerical simulations show the magnitude of the equivalent permeabilities and local profiles, such as displacement jumps, as a function of the stress state, characterized by the pore pressure and overburden stresss. Finally, we present comparisons between the outcomes of each technique.
Synthetic Benchmark for the Computation of Equivalent Properties in Coupled Flow-Geomechanical Scenarios for a Fractured Carbonate Rock
Falcao, Flavia, Barroso, Josue, Murad, Marcio, Pereira, Patricia, Vargas, Eurípedes, Juvinao, Alonso, Muller, André, Roehl, Deane, Quevedo, Roberto, Mejia, Cristian, Guimaraes, Leonardo, Beserra, L., Alvarez, L., Cleto, Pedro, and Osvaldo Manzoli. "Synthetic Benchmark for the Computation of Equivalent Properties in Coupled Flow-Geomechanical Scenarios for a Fractured Carbonate Rock." Paper presented at the 2nd International Discrete Fracture Network Engineering Conference, Seattle, Washington, USA, June 2018.
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