Mechanical properties of siliceous rocks around the Horonobe URL from triaxial compression and isotropic consolidation tests
As part of the research and development program on geological disposal of a high-level radioactive waste, the Horonobe Underground Research Center, a division of the Japan Atomic Energy Agency (JAEA), has been implementing the Horonobe Underground Research Laboratory(URL) Project. This paper describes mechanical properties of siliceous rocks distributing around the Horonobe URL on the basis of triaxial compression and isotropic consolidation tests. The triaxial tests were carried out under drained and undrained conditions since pore structure change in the sedimentary soft rocks with large effective porosity was expected. The stress-strain behavior changed from strain-softening to ductle behavior with high effective confining pressure and the pore pressure increased gradually even after the peak strength for the diatomaceous mudstone. On the other hand, strain-softening behavior was founded in total duration of the tests regardless of the effective confining pressure value and the pore pressure decreased rapidly after the peak stress for the siliceous mudstone. The diatomaceous mudstone yielded under hydrostatic pressure of 10 MPa in isotropic consolidation. This yielding was regarded as pore collapse due to the change of hydraulic conductivity which was estimated from volume change under isotropic consolidation test, effective porosity and microscopic observation before and after the yielding.
H.Sanada H.Matsui Y.Fujii
Japan Atomic Energy Agency, Japan Hokkaido University, Japan
国际会议
香港
英文
1-5
2009-05-19（万方平台首次上网日期，不代表论文的发表时间）