The project aims at increasing the conceptual understanding of the hydromechanical properties of crystalline rock. These properties are influenced by the geological history of the site at hand as well as the current effective stress situation. Fracture stiffness is a property of particular interest in the project. The conceptual understanding is built around laboratory experiments and experiments in boreholes close to tunnels. An increased understanding of the hydromechanical properties enables improved prognoses and modeling for the safety assessment of the proposed Swedish nuclear waste repository. More effective sealing of fractures and use of underground space are areas that can be developed from the project. The project is accompanied by several other PhD-projects within the Rock Mechanics Research Programme at the Swedish Nuclear Fuel and Waste Management Co.

Fracture geometry, rock mechanical properties and hydrogeological properties are used with several ”boundary conditions” for achieving a reasonable description of the hydromechanical properties.
This project is related to the projects Hydromechanical behaviour of fractures in-situ: Conceptual model and field data analysis and Bentonite Rock Interaction Experiment.
The project is carried out at the Division of GeoEngineering, research group Geotechnical Engineering.
Keywords: Hydromechanical coupling, Fracture stiffness, Geological history, Fracture geometry, Hydrogeology, Rock mechanics
Project leader
Åsa Fransson
Project members
Johan Thörn
Åsa Fransson
Lars O Ericsson
Contact
Johan Thörn
Swedish Nuclear Fuel and Waste Management Co, SKB