1. Swedish National Road and Transport Research Institute, VTI, SE-581 95 Linköping, Sweden
2. Department of Mechanics and Maritime Sciences/CHARMEC, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden
3. Geology and Geotechnics, Department of Architecture and Civil Engineering, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden