Electromagnetic response during failure process including pre-phenomenon of gouge-bearing rock

• Project/Area Number: 23651173
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Natural disaster science
• Research Institution: Osaka City University
• Principal Investigator: NAKAGAWA Koichi 大阪市立大学, 都市研究プラザ, 名誉教授 (80047282)
• Project Period (FY): 2011 – 2013
• Project Status: Completed (Fiscal Year 2013)
• Budget Amount: ¥3,770,000 (Direct Cost: ¥2,900,000、Indirect Cost: ¥870,000); Fiscal Year 2013: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000); Fiscal Year 2012: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000); Fiscal Year 2011: ¥2,210,000 (Direct Cost: ¥1,700,000、Indirect Cost: ¥510,000)
• Keywords: せん断分極 / 断層粘土 / 岩盤破壊 / 震源過程 / 地すべり / 間隙水の化学 / 破壊予測 / 年度の物理化学 / ガウジ / スティックスリップ / 自然電位 / 地震予知 / せん断分局 / 粘土特性 / Shear-Induced Potential / 破壊予知 / 粘土の物理化学作用

Research Abstract

It has been clarified that the gouge is polarized electrically (SIP: Shear-induced Polarization) by shear deformation. To solve the mechanism of SIP, the time variation of electrolyte concentration was measured in pore water of the kaolinite squeezed out under the compaction loading. The changing manner of the electrolyte concentration depends on the magnitude of compaction load, however, the concentration decreases with time generally. On the other hand, in the large loading cycle, the rapid increasing of the concentration was observed during the primary consolidation. This rapid increasing of the electrolyte concentration is interpreted as result of the collapsing inter-particle bonding of the clay by the shearing. General decreasing of the concentration during the secondary consolidation may be recognized as result of structuring the inter-particle bonding in the clay.

Research Products

• [Presentation] ガウジの変わった性質とすべり破壊予測の可能性 (2013)
  • Author(s): 中川康一
  • Organizer: 日本活断層学会
  • Place of Presentation: つくば国際会議場, つくば
  • Year and Date: 2013-11-29
• [Presentation] Effects of vibration by demolition to nearby machine shop floor-wave measurement for dynamic property of ground (2013)
  • Author(s): Y. Iwasaki and K. Nakagawa
  • Organizer: Fourth International Seminar on Forensic Geotechnical Engineering
  • Place of Presentation: Bengaluru, India
  • Year and Date: 2013-01-11
• [Presentation] 仏念寺山断層帯に現れた断層露頭とその破砕特性 (2013)
  • Author(s): 中川康一
  • Organizer: 日本活断層学会
  • Place of Presentation: つくば国際会議場, つくば
• [Presentation] ガウジの変わった性質とすべり破壊予測の可能性 (2013)
  • Author(s): 中川康一
  • Organizer: 日本活断層学会
  • Place of Presentation: つくば国際会議場
• [Presentation] 仏念寺山断層帯に現れた断層露頭とその破砕特性 (2013)
  • Author(s): 中川康一
  • Organizer: 日本活断層学会
  • Place of Presentation: つくば国際会議場
• [Presentation] Resistivity profiles and foundation structure of Central Tower, Bayon in Angkor, Geoengineering for construction and conservation of cultural heritage and historical sites (2012)
  • Author(s): K. Nakagawa, I. Shimoda, S. Yamada, R. Kanai, Y. Ogawa, Y. (Yasuda) Ohta, M. Fukuda, A. Jomori, T. Takahashi and Y. Iwasaki
  • Organizer: Central Asian Geotechnical Symposium (IVth CAGS)
  • Place of Presentation: Samarkand, Uzbekistan
  • Year and Date: 2012-09-23
• [Presentation] Resistivity profiles and foundation structure of Central Tower, Bayon in Angkor (2012)
  • Author(s): K. Nakagawa, I. Shimoda, S. Yamada, R. Kanai, Y. Ogawa, Y. (Yasuda) Ohta, M. Fukuda, A. Jomori, T. Takahashi and Y. Iwasaki
  • Organizer: Central Asian Geotechnical Symposium (IVth CAGS),Geo-engineering for construction and conservation of cultural heritage and histrical sites
  • Place of Presentation: Samarkand