Pre-failure deformation of geomaterials : proceedings of the first international on pre-failure deformation characteristics of geomaterials Sapporo, Japan, 12-14 September 1994 / 由 International Conference on Pre-Failure Deformation Characteristics of Geomaterials (1st : 1994 : Sapporo, Japan), Toshiyuki, Mitachi, Satoru, Shibuya, Seiichi, Miura