Couplings between damage, failure and transport
in tight quasi-brittle materials

Abstract

Tight quasi-brittle materials are micro and meso-porous materials characterized by a very low permeability (less than a tenth of a millidarcy). Failure of such quasi-brittle materials is characterized by the presence of a fracture process zone (FPZ) where micro-cracks appear, evolve and interact in the course of damage. When the distribution of cracks and the distribution of pore size evolve in such tight quasi-brittle materials, the influence on the permeability in the case of a single or a multiphase fluid flow needs some in depth investigation.

People

Current people in the group:

Alumni:

Olivier Nouailletas
Postdoc fellow
Fracture and permeability of heterogeneous quasi-brittle media(24 months 2013/2015)Now: research engineerSIAME ISABTP UPPA

Akli Kahlal
MSc student

Experimental investigation on adsorption, deformation and transport couplings in microporous materials(MSc defense 13-09-2021)
Laura Rojas-Solano
PhD student
Non-local damage, interactions and size effect(PhD defense 07-12-2012)Now: Field Perf. Analyst, Goodyear, Luxembourg.
Fadi Khaddour
PhD student
Production enhancement of Tight Gas Reservoirs(PhD defense 11-04-2014)Now: Assistant ProfessorAl-Baath Univ. Holms, Syria
Fabrizio Croccolo
Postdoc fellow
Experimental determination of a saturation front in a porous medium(12 months 2014/2015)Now: E2S Chair ProfessorLFCR UPPA
Laurent Perrier
Postdoc fellow
Coupling between adsorption/deformation/transport in porous media(24 months 2015/2017)Now: Assistant ProfessorLFCR, UPPA
Vincent Lefort
PhD student
A lattice model for crack propagation simulation under fluid injection in a quasi-brittle heterogeneous medium(PhD defense 04-07-2016)Now: Eng. school teacherISABTP, UPPA
Lionel Ecay
MSc/PhD student
Concrete transfer properties evolution and nuclear containment vessel tightness assessment during an accident(MSc defense 01/09/2014)(PhD defense 17-12-2018)Now: structural engineer
at Ingeni, Switzerland

Other collaborators:

Connected publications

Multi-stage micrite diagenesis in the late Jurassic of the Eastern Paris Basin: petrophysical and mechanical properties for engineering purposesThe “Calcaires du Barrois” Formation is a succession of dominantly micritic limestone of Kimmeridgian to Tithonian age, outcropping in the eastern part of the Paris Basin. This is an active karstic aquifer of main interest for the Andra (French National Agency for Radioactive Waste Management) who study the feasibility of a deep geological repository of radioactive waste in an Underground Research Laboratory (URL) located approximately 450m below the surface. Surface installations of the CIGEO (Industrial Centre for Geological Disposal) project are planned to be located in the upstream recharge zone of the aquifer. It is of primary interest to characterise the “Calcaires du Barrois” Formation to provide guidelines for the planning and the sizing of these facilities, with the objective of minimising the impact on the aquifer system. An integrated study was designed for this purpose linking petrography (thin section, and SEM, Scanning Electron Microscope), C & O stable isotope geochemistry, XRD (X-Ray Diffraction), petrophysics and geomechanics, and based on the analysis of three key cored wells penetrating the formation at different relative depths. The “Calcaires du Barrois” underwent several stages of diagenesis that defined the current properties. Unconformities associated with the Jurassic-Cretaceous transition led to prolonged early subaerial exposures during which freshwater flowed efficiently through the upper half of the formation. Through mineralogical stabilisation, among other processes, microporosity was preserved in micrites in this interval consisting of clean limestone with thin marl layers. The lower half of the formation, more argillaceous, was not or only slightly affected by this early meteoric diagenesis and recrystallization and cementation of micrites occurred during burial diagenesis, involving chemical compaction. Later, during the return to the surface associated to the Cenozoic orogens, another phase of meteoric diagenesis affected the uppermost few metres below the outcropping portions of the formation, but without modifying significantly the previously acquired petrophysical properties. Consequently, an intra-formational boundary was progressively developed at around 75m (from the top reference). This boundary separates (1) a lower half of the “Calcaires du Barrois” with dense and tight micrites, showing high Young's Modulus values, and a moderate intensity of fractures, from (2) a upper half with microporous micrites showing low Young's Modulus values, and almost devoid of fractures. A transitional zone of about 30m-thick, with intermediate properties, sitting above this boundary and below the only thin metre-scale macroporous grainstone level of the formation, accommodated most of the deformation linked to the Cenozoic west-European orogens and is intensively fractured. The current hydrogeological model considers a purely sedimentological boundary to delimit two sub-aquifers within the “Calcaires du Barrois” Formation, but will have to be reappraised since it is here demonstrated that the real boundary is located significantly higher in the formation and is inherited from a multi-stage diagenetic history. These findings will complement and influence planning for engineering of the CIGEO project.
Multi-stage micrite diagenesis in the late Jurassic of the Eastern Paris Basin: petrophysical and mechanical properties for engineering purposesThe “Calcaires du Barrois” Formation is a succession of dominantly micritic limestone of Kimmeridgian to Tithonian age, outcropping in the eastern part of the Paris Basin. This is an active karstic aquifer of main interest for the Andra (French National Agency for Radioactive Waste Management) who study the feasibility of a deep geological repository of radioactive waste in an Underground Research Laboratory (URL) located approximately 450m below the surface. Surface installations of the CIGEO (Industrial Centre for Geological Disposal) project are planned to be located in the upstream recharge zone of the aquifer. It is of primary interest to characterise the “Calcaires du Barrois” Formation to provide guidelines for the planning and the sizing of these facilities, with the objective of minimising the impact on the aquifer system. An integrated study was designed for this purpose linking petrography (thin section, and SEM, Scanning Electron Microscope), C & O stable isotope geochemistry, XRD (X-Ray Diffraction), petrophysics and geomechanics, and based on the analysis of three key cored wells penetrating the formation at different relative depths. The “Calcaires du Barrois” underwent several stages of diagenesis that defined the current properties. Unconformities associated with the Jurassic-Cretaceous transition led to prolonged early subaerial exposures during which freshwater flowed efficiently through the upper half of the formation. Through mineralogical stabilisation, among other processes, microporosity was preserved in micrites in this interval consisting of clean limestone with thin marl layers. The lower half of the formation, more argillaceous, was not or only slightly affected by this early meteoric diagenesis and recrystallization and cementation of micrites occurred during burial diagenesis, involving chemical compaction. Later, during the return to the surface associated to the Cenozoic orogens, another phase of meteoric diagenesis affected the uppermost few metres below the outcropping portions of the formation, but without modifying significantly the previously acquired petrophysical properties. Consequently, an intra-formational boundary was progressively developed at around 75m (from the top reference). This boundary separates (1) a lower half of the “Calcaires du Barrois” with dense and tight micrites, showing high Young's Modulus values, and a moderate intensity of fractures, from (2) a upper half with microporous micrites showing low Young's Modulus values, and almost devoid of fractures. A transitional zone of about 30m-thick, with intermediate properties, sitting above this boundary and below the only thin metre-scale macroporous grainstone level of the formation, accommodated most of the deformation linked to the Cenozoic west-European orogens and is intensively fractured. The current hydrogeological model considers a purely sedimentological boundary to delimit two sub-aquifers within the “Calcaires du Barrois” Formation, but will have to be reappraised since it is here demonstrated that the real boundary is located significantly higher in the formation and is inherited from a multi-stage diagenetic history. These findings will complement and influence planning for engineering of the CIGEO project.

Connected projects

Newpores - New Frontiers in Porous Materials

Granted by E2S UPPA, NewPores is an international hub dedicated to the mechanics and physics of porous materials, which intends to answer to new Energy and Environment challenges. This is a joint effort of the group on Geomechanics and Porous Materials (G2MP) of the Laboratoire des Fluides Complexes et leurs Réservoirs at E2S UPPA (France), the Centre for Sustainable Engineering of Geological and Infrastructure Materials (SEGIM) at Northwestern University (USA), the University of Vigo (Spain), the Technical University of Madrid (Spain) and University of Liège (Belgium).

Propriétés de transport et échanges en milieux poreux : détermination de la tortuosité

Dans le contexte d’une construction durable, les échanges et transferts au sein des matériaux poreux sont de première importance. On cherche notamment à minimiser les échanges thermiques pour limiter les pertes, les échanges phoniques pour limiter les nuisances tout en gardant des matériaux « respirant » afin d’assurer une bonne qualité de l’air intérieur. Dans le cadre de filtres ou de matériaux de construction, les propriétés de transport, comme la perméabilité (aptitude à se laisser traverser par un fluide de référence sous l’effet d’un gradient de pression) ou la diffusion (tendance naturelle d’un système à rendre homogènes les inégalités en son sein), sont caractérisées par la géométrie du squelette poreux, notamment la distribution de taille de pore, leur connectivité et la tortuosité du milieu poreux. La tortuosité est le rapport entre la longueur du trajet réel réalisé par une particule pour traverser le milieu poreux et sa longueur caractéristique, c’est donc un paramètre essentiel lorsque l’on cherche à évaluer les propriétés de transport du milieu.

MACENA - Tightness assessment of confinement vessels during an accident

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FAILFLOW - Failure and Fluid Flow in Porous Quasibrittle Materials

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