Pore water pressure evolution below a freezing front under saturated conditions: Large-scale laboratory experiment and numerical investigation

• Published in: Cold Regions Science and Technology
• Main Authors: Rivière, Agnès, Jost, Anne, Goncalves, Julio, Font, Marianne
• Other Authors: Centre de Géosciences (GEOSCIENCES), Mines Paris - PSL (École nationale supérieure des mines de Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Milieux Environnementaux, Transferts et Interactions dans les hydrosystèmes et les Sols (METIS), École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Morphodynamique Continentale et Côtière (M2C), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2019
• Subjects: Frost heave; Large-scale laboratory experiment; Numerical simulations; Subpermafrost aquifer; Excess pore-water pressure; Freeze-thaw cycle; Ice expansion; [PHYS.PHYS.PHYS-FLU-DYN]Physics [physics]/Physics [physics]/Fluid Dynamics [physics.flu-dyn]; [SPI.FLUID]Engineering Sciences [physics]/Reactive fluid environment; [SHS.GESTION]Humanities and Social Sciences/Business administration; [SHS.ENVIR]Humanities and Social Sciences/Environmental studies; [SDE.MCG]Environmental Sciences/Global Changes; [SDV.EE.ECO]Life Sciences [q-bio]/Ecology; environment/Ecosystems; [SDV.EE.BIO]Life Sciences [q-bio]/Ecology; environment/Bioclimatology; [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry; [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology; [SDE.ES]Environmental Sciences/Environment and Society; [SDU.STU.HY]Sciences of the Universe [physics]/Earth Sciences/Hydrology; [SDE.BE]Environmental Sciences/Biodiversity and Ecology; [SDE.IE]Environmental Sciences/Environmental Engineering; [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces; environment; [PHYS.MECA.THER]Physics [physics]/Mechanics [physics]/Thermics [physics.class-ph]; Ice; permafrost
• Online Access: https://hal.science/hal-02404162; https://doi.org/10.1016/j.coldregions.2018.11.005

(IF 2.74; Q1) International audience Subpermafrost aquifer hydrodynamics is generally poorly known due to monitoring technology issues. The few available data show that this aquifer is confined below continuous permafrost due to ice expansion. We conducted a 2 m × 1 m × 1 m sand box experiment under controlled conditions in a cold room to (1) evaluate the confinement of the unfrozen part of a saturated porous medium below a propagating freezing/thawing front, (2) assess the associated uplift of the soil surface, and therefore (3) quantify how the ice expansion translates into frost heave and excess pore-water pressure in the unfrozen part below the freezing soil. Pore water pressure, soil temperature and soil heave were monitored inside the sand box during a 70-day freeze-thaw cycle. A transient fully coupled heat transport and water flow model (called Ginette) was developed to reproduce the freeze-thaw experiment numerically. It takes into account excess pore-water pressure related to pore water phase changes and uses a simple hydro-mechanical term based on the storage coefficient to estimate soil heave. Fairly good agreement was obtained between measured and simulated pressure heads in the unfrozen part below the freezing front over time. Both experimental and numerical approaches show that the ice expansion is translated into excess pore-water pressure (maximum pore water pressure: 5.5 m) and frost heave (2.2 cm).