Steel waste canisters, bentonite clay and cement backfills constitute the multi barrier concept for the deep geological disposal of radioactive waste. The aim of this research project was to deploy and refine advanced monitoring technologies for simultaneous imaging of THMC variables (pH, temperature, pore-water pressure, swelling etc) within these elements of the multi-barrier systemi n these elements of the multi barrier system in these elements of the multi barrier system in these elements ofin the laboratory. State-of-the-art micro-to-nano scale wireless devices were embeded into bentonite, and, combined with micro-scale geophysical and magnetic monitoring surveys, 2D and 3D heterogeneities in THMC behaviour were illumnated. These monitoring technologies were integrated with experiments to gain a predictive understanding of the THMC evolution of clay-based engineered barriers, and their interfaces, up to the upper-bound of realistic environmental conditions. Interfaces comprised of joints within the clay as well as interfaces to the surrounding rock, cement and waste container. Experiments and modelling focused on the effects of strong gradients in temperature (<150 degrees C), low pH cements and high salinity (10-40 g/l) across the EBS interfaces, and on the fingering of flow along joints and interfaces that may give rise to a heterogeneous THMC system response.
|Effective start/end date||30/09/12 → 29/03/17|