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 1m 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 5.1m into the host rock, the influence of the excavation on permeability is limited.
|Title of host publication||EDZ around an industrial excavation in Boom Clay|
|Place of Publication||Luxembuourg, Luxembourg|
|State||Published - Nov 2005|
|Event||Impact of the excavation disturbed or damged zone (EDZ) on the performance of radioactive waste geological repositories - Luxembourg|
Duration: 30 Nov 2005 → 30 Nov 2005
|Conference||Impact of the excavation disturbed or damged zone (EDZ) on the performance of radioactive waste geological repositories|
|Period||2005-11-30 → 2005-11-30|