CPL - Chalmers Publication Library
| Utbildning | Forskning | Styrkeområden | Om Chalmers | In English In English Ej inloggad.

Hydromechanical characterization of fractures close to a tunnel opening: A case study

Åsa Fransson (Institutionen för bygg- och miljöteknik, Geologi och geoteknik) ; Johan Thörn (Institutionen för bygg- och miljöteknik, Geologi och geoteknik) ; Lars O. Ericsson (Institutionen för bygg- och miljöteknik, Geologi och geoteknik) ; Margareta Lönnqvist (Institutionen för bygg- och miljöteknik, Geologi och geoteknik) ; Martin Stigsson (Institutionen för bygg- och miljöteknik, Geologi och geoteknik)
Eurock2012, 28-30 May, Stockholm, Sweden (2012)
[Konferensbidrag, refereegranskat]

Important factors influencing the hydromechanical behavior of a fracture are in situ rock stresses (natural and induced) as well as hydraulic heads, fracture orientation, connectivity and fracture geometry, including their infillings. Particular attention is given to larger, water-conducting fractures that intersect or are close to a tunnel. For the Bentonite Rock Interaction Experiment (BRIE) at the Äspö Hard Rock Laboratory (HRL) in Sweden, the interaction between rock and bentonite in a deposition borehole is of particular interest. The BRIE experiment is being conducted at a depth of 420 meters in crystalline rock. This paper presents results from the initial identification, characterization and modeling of a small number of fractures close to the tunnel opening. So far, these fractures have been identified as the most important water-conducting fractures. In this identification and characterization exercise, core-drilled, vertical, three-meter deep investigation boreholes were made in the tunnel floor. Logging of natural hydraulic heads in boreholes and hydraulic tests, along with borehole and tunnel mapping in combination with modeling, indicate small deformations. This was also confirmed by deformation measurements performed in the boreholes. The description of the site will be further updated and revised and additional investigations into the link between stress history, fracture geometry and selection of fracture mechanical properties will be of particular interest.

Nyckelord: Hydromechanical, characterization, fractures, tunnel opening

Den här publikationen ingår i följande styrkeområden:

Läs mer om Chalmers styrkeområden  

Denna post skapades 2012-06-14. Senast ändrad 2014-11-27.
CPL Pubid: 158944