Instrumentation for a gas path through host rock and along sealing experiment

A key issue in the field of underground waste storage is the investigation of the barrier function of the host rock and the sealing of the disposal tunnel. For the demonstration of gas escape, a large scale "gas path through host rock and along sealing experiment" is currently being conducted at the Mont Terri Rock Laboratory in Switzerland. The experiment is focused on the gas paths along an excavation damaged zone (EDZ) developed around a sealed microtunnel section and the gas paths through the excavation undisturbed host rock. The instrumentation of the test site comprises suitable sensors to assess the hydraulic and geo-mechanic characteristics and the coupled hydromechanical processes around the tunnel. The first test data show a good response of the sensors to the induced pressures and stresses.