Poroelastic coefficients for siliceous rocks distributed in the Horonobe area, Hokkaido, Japan

Miyazawa, Daisuke*; Sanada, Hiroyuki; Kiyama, Tamotsu*; Sugita, Yutaka ; Ishijima, Yoji*

The geology around the Japanese coast exhibits a wide distribution of mudstones composed of fossil diatoms and silica rocks. These bedrocks are categorized as porous and low permeability rock. When underground openings at rocks with such rock mechanics properties are constructed, evaluation which takes into account flow-stress coupling behavior is required. Poroelasticity treats both pore fluids and the mineral particles which make up rocks as compressible. Consequently, its application can extend to rock that is harder than soil materials. In this study, laboratory experiments by using the siliceous rocks distributed in the Horonobe area, Hokkaido, Japan were carried out as a case study. Proposal method for obtaining poroelasic coefficients as well as determination of poroelastic coefficients distributed in the Horonobe area are described in this paper.