Highly compacted bentonite buffers are planned to be used as engineered barriers in the near-field of nuclear waste repositories in crystalline formations. The erosion of these bentonite buffers at the boundary to the surrounding Excavation Disturbed Zone (EDZ) can be a source of colloids leading to a notable concentration of colloids in the EDZ water, which is high above the natural colloid co...

The support theory of the excavation disturbance zone (EDZ) cannot provide an accurate physical explanation or theoretical description time-dependent properties required for development EDZ. Therefore, primary factors that cause formation EDZ should be determined to further improve and grasp principle underlying control long-term stability rock masses. Considering headrace tunnel nuclear waste ...

We present the results of new and repeat gallery- borehole-scale seismic experiments carried out in two excavation damaged zones (EDZs) 10 (gallery 08) 20 98) years age at Mont Terri Underground Rock Laboratory St. Ursanne, Switzerland. The initial geometry rock mass properties EDZs were studied during shortly after excavation—allowing for a direct comparison measurements collected 2018 to thos...

Swelling of clay-sulfate rocks is a major threat in tunneling. It is triggered by the transformation of the sulfate mineral anhydrite into gypsum as a result of water inflow in anhydrite-containing layers after tunnel excavation. The present study investigates the hydraulic effects of tunneling on groundwater flow and analyzes how hydraulic changes caused by excavation lead to water inflow into...