ダウンロード数: 210
このアイテムのファイル:
ファイル | 記述 | サイズ | フォーマット | |
---|---|---|---|---|
(ASCE)GM.1943-5622.0002114.pdf | 1.3 MB | Adobe PDF | 見る/開く |
タイトル: | Short- and Long-Term Observations of Fracture Permeability in Granite by Flow-Through Tests and Comparative Observation by X-Ray CT |
著者: | Song, Chenlu Nakashima, Shinichiro Kido, Ryunosuke https://orcid.org/0000-0002-5204-0130 (unconfirmed) Yasuhara, Hideaki https://orcid.org/0000-0003-4557-4692 (unconfirmed) Kishida, Kiyoshi https://orcid.org/0000-0003-1588-4024 (unconfirmed) |
著者名の別形: | 宋, 忱潞 木戸, 隆之祐 安原, 英明 岸田, 潔 |
キーワード: | Permeability Short- and long-term tests X-ray CT observation Contact-area ratio and aperture distribution |
発行日: | Sep-2021 |
出版者: | American Society of Civil Engineers (ASCE) |
誌名: | International Journal of Geomechanics |
巻: | 21 |
号: | 9 |
論文番号: | 04021151 |
抄録: | Having a grasp of the variation in the fracture contact area is a kernel in the understanding of the permeability evolution of fractured rocks. However, the number of studies that focus on measuring the long-term variation in the fracture contact area under different conditions is insufficient. In this study, a series of short- and long-term permeability tests under coupled conditions is performed to check the performance of permeability. The results reveal that the permeability measured in the short-term tests shows reversible behavior and a dependence on the applied confining pressures and temperature. In contrast, the permeability in the long-term tests displays irreversible behavior and an irregular change under the constant confining pressure. In order to verify the evolution of permeability, microfocus X-ray computed tomography (CT) is developed to observe the changes in the internal fracture structure under the same conditions as those in long-term permeability tests by assembling a triaxial cell with heating capability. The fracture aperture and the fracture contact-area ratio are calculated by a CT image analysis technique. The image analysis results show that the estimated aperture is seen to decrease with an increase in the confining pressure and to also decrease with time under a constant confining pressure. Moreover, the increase in the fracture contact area under the constant confining pressure observed by X-ray CT is confirmed. This also corresponds to a decrease in permeability in long-term tests. The hydraulic aperture calculated from the permeability tests and that evaluated from the CT observation have a similar decreasing trend. Therefore, the CT observation can better capture the evolution of the internal fracture contact area. These experiments underscore the importance of mechanical compaction and/or mineral dissolution at contacts in determining the rates and the magnitude of permeability evolution within rock fractures. |
著作権等: | This material may be downloaded for personal use only. Any other use requires prior permission of the American Society of Civil Engineers. This material may be found at https://ascelibrary.org/doi/10.1061/(ASCE)GM.1943-5622.0002114. This is not the published version. Please cite only the published version. この論文は出版社版でありません。引用の際には出版社版をご確認ご利用ください。 |
URI: | http://hdl.handle.net/2433/264255 |
DOI(出版社版): | 10.1061/(ASCE)GM.1943-5622.0002114 |
出現コレクション: | 学術雑誌掲載論文等 |
このリポジトリに保管されているアイテムはすべて著作権により保護されています。