EDZ around an Industrial Excavation in Boom Clay

Wim Bastiaens, J. Mertens

    Research outputpeer-review

    Abstract

    A new gallery (excavated diameter 4.89m) was recently constructed at the underground re­search facility HADES (Mol, Belgium) located at a depth of 223m in a plastic clay layer. An industrial excavation technique was used. The EDZ around the gallery is studied by observing macro-fractures and pore pressure distribution. The fractured zone extends at least lm into the host rock; this value will be verified during the EC SELFRAC project. The radius of the Hy­draulic Disturbed Zone (HDZ) is at least 20m and the HDZ is anisotropic. Gallery construc­tion will always induce an EDZ but it is shown that industrial excavation techniques can limit its extent. From a depth of 1.3m into the host rock, installed piezometers are sealed off from the gallery by the converging clay. From a distance of 5. lm into the host rock, the influence of the excavation on permeability is limited.
    Original languageEnglish
    Title of host publicationEuropean Commission cluster conference and workshop on the impact of the excavation disturbed or damaged zone on the performance of radioactive waste geological repositories
    EditorsC. Davies, F. Bernier
    PublisherEC - European Commission
    Pages305-309
    Number of pages5
    ISBN (Print)92-894-8794-1
    StatePublished - Nov 2003
    Event2003 - European Commission cluster conference and workshop on the impact of the excavation disturbed or damaged zone on the performance of radioactive waste geological repositories - Luxemburg
    Duration: 3 Nov 20035 Nov 2003

    Publication series

    NameEUR reports
    PublisherOffice for official publications of the European Communities
    NumberEUR-21028

    Conference

    Conference2003 - European Commission cluster conference and workshop on the impact of the excavation disturbed or damaged zone on the performance of radioactive waste geological repositories
    Country/TerritoryLuxembourg
    CityLuxemburg
    Period2003-11-032003-11-05

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