TY - JOUR
T1 - Dynamics of fracturing saturated porous media and self-organization of rupture
AU - Peruzzo, C.
AU - Cao, D. T.
AU - Milanese, E.
AU - Favia, P.
AU - Pesavento, F.
AU - Hussain, F.
AU - Schrefler, B. A.
N1 - Funding Information:
The authors thank Professor H.J. Herrmann for most useful comments. The work of B.A. Schrefler, has been carried out with the support of the Technische Universität München - Institute for Advanced Study, funded by the German Excellence Initiative and the TÜV SÜD Foundation. C. Peruzzo and F. Pesavento were supported by the project 734370-BESTOFRAC (“Environmentally best practices and optimisation in hydraulic fracturing for shale gas/oil development”)-H2020-MSCA-RISE-2016.
Funding Information:
The authors thank Professor H.J. Herrmann for most useful comments. The work of B.A. Schrefler, has been carried out with the support of the Technische Universität München - Institute for Advanced Study, funded by the German Excellence Initiative and the TÜV SÜD Foundation . C. Peruzzo and F. Pesavento were supported by the project 734370-BESTOFRAC (“ Environmentally best practices and optimisation in hydraulic fracturing for shale gas/oil development ”)- H2020-MSCA-RISE-2016 .
Publisher Copyright:
© 2019 Elsevier Masson SAS
PY - 2019/3/1
Y1 - 2019/3/1
N2 - Analytical solutions and a vast majority of numerical ones for fracture propagation in saturated porous media yield smooth behavior while experiments, field observations and a few numerical solutions reveal stepwise crack advancement and pressure oscillations. To explain this fact, we invoke self-organization of rupture observed in fracturing solids, both dry and fully saturated, when two requirements are satisfied: i) the external drive has a much slower timescale than fracture propagation; and ii) the increment of the external load (drive) is applied only when the internal rearrangement of fracture is over. These requirements are needed to obtain clean Self Organized Criticality (SOC) in quasi-static situations. They imply that there should be no restriction on the fracture velocity i.e. algorithmically the fracture advancement rule should always be independent of the crack velocity. Generally, this is not the case when smooth answers are obtained which are often unphysical. Under the above conditions hints of Self Organized Criticality are evident in heterogeneous porous media in quasi-static conditions using a lattice model, showing stepwise advancement of the fracture and pressure oscillations. We extend this model to incorporate inertia forces and show that this behavior still holds. By incorporating the above requirements in numerical fracture advancement algorithms for cohesive fracture in saturated porous continua we also reproduce stepwise advancements and pressure oscillations both in quasi-static and dynamic situations. Since dynamic tests of dry specimens show that the fracture advancement velocity is not constant we replicate such an effect with a model of a debonding beam on elastic foundation. This is the first step before introducing the interaction with a fluid.
AB - Analytical solutions and a vast majority of numerical ones for fracture propagation in saturated porous media yield smooth behavior while experiments, field observations and a few numerical solutions reveal stepwise crack advancement and pressure oscillations. To explain this fact, we invoke self-organization of rupture observed in fracturing solids, both dry and fully saturated, when two requirements are satisfied: i) the external drive has a much slower timescale than fracture propagation; and ii) the increment of the external load (drive) is applied only when the internal rearrangement of fracture is over. These requirements are needed to obtain clean Self Organized Criticality (SOC) in quasi-static situations. They imply that there should be no restriction on the fracture velocity i.e. algorithmically the fracture advancement rule should always be independent of the crack velocity. Generally, this is not the case when smooth answers are obtained which are often unphysical. Under the above conditions hints of Self Organized Criticality are evident in heterogeneous porous media in quasi-static conditions using a lattice model, showing stepwise advancement of the fracture and pressure oscillations. We extend this model to incorporate inertia forces and show that this behavior still holds. By incorporating the above requirements in numerical fracture advancement algorithms for cohesive fracture in saturated porous continua we also reproduce stepwise advancements and pressure oscillations both in quasi-static and dynamic situations. Since dynamic tests of dry specimens show that the fracture advancement velocity is not constant we replicate such an effect with a model of a debonding beam on elastic foundation. This is the first step before introducing the interaction with a fluid.
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U2 - 10.1016/j.euromechsol.2018.12.004
DO - 10.1016/j.euromechsol.2018.12.004
M3 - Article
AN - SCOPUS:85060007686
SN - 0997-7538
VL - 74
SP - 471
EP - 484
JO - European Journal of Mechanics, A/Solids
JF - European Journal of Mechanics, A/Solids
ER -