Study on the mechanism of reactivated landslide induced by the seasonal fluctuations in ground temperature

• Project/Area Number: 26560190
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Natural disaster / Disaster prevention science
• Research Institution: Kyoto University
• Principal Investigator: Matsuura Sumio 京都大学, 防災研究所, 教授 (10353856)
• Co-Investigator(Kenkyū-buntansha): 岡本 隆 国立研究開発法人森林総合研究所, その他部局等, チーム長 (30353626)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Project Status: Completed (Fiscal Year 2016)
• Budget Amount: ¥3,640,000 (Direct Cost: ¥2,800,000、Indirect Cost: ¥840,000); Fiscal Year 2016: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000); Fiscal Year 2015: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000); Fiscal Year 2014: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000)
• Keywords: 積雪地帯 / 再活動型地すべり / 地温 / スメクタイト / リングせん断試験 / 残留強度 / 温度効果 / 地すべり / 膨潤性粘土鉱物 / 膨張性粘土鉱物

Outline of Final Research Achievements

We investigated the effect of seasonal fluctuation in ground temperature on shallow landslides occurring in the cold season from late autumn to early winter. The effect of temperature on shear strength was investigated on undisturbed smectite-rich slip surface soils collected from Busuno landslide, Niigata Prefecture. Test results showed that shear strength decreases with decreasing temperature and slow creep-like displacements can be induced by cooling. Ring shear experiments performed on many slip surface soils also demonstrated that this temperature effect on residual strength is typical for smectite-rich soils and prevail at slow shearing rate conditions in which platy smectite particles are highly oriented along the shear surface.

Research Products

• [Journal Article] Temperature-dependent residual shear strength characteristics of smectite-bearing landslide soils (2017)
  • Author(s): Shibasaki T., Matsuura S. and Hasegawa Y.
  • Journal Title: Journal of Geophysical Research: Solid Earth Volume: 122(2) Issue: 2 Pages: 1449-1469
  • DOI: 10.1002/2016jb013241
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] Experimental evidence for shallow, slow-moving landslides activated by a decrease in ground temperature (2016)
  • Author(s): Shibasaki T., Matsuura S. and Okamoto T.
  • Journal Title: Geophysical Research Letters Volume: 43(12) Issue: 13 Pages: 6975-6984
  • DOI: 10.1002/2016gl069604
  • Peer Reviewed / Acknowledgement Compliant
• [Presentation] スメクタイトを含む粘土のリングせん断挙動に及ぼす交換性陽イオンの影響 (2016)
  • Author(s): 柴崎達也，松浦純生，岡本隆，長谷川陽一
  • Organizer: 第55回日本地すべり学会研究発表会講演集
  • Place of Presentation: 高知県立県民文化ホール
  • Year and Date: 2016-08-24
• [Presentation] A possible mechanism to explain reactivated landslides which begin to move in the early cold season (2015)
  • Author(s): Shibasaki T., Matsuura S., and Okamoto T.
  • Organizer: Proceeding of 10th Asian regional conference of IAEG, Kyoto
  • Place of Presentation: Kyoto University, Uji Obaku Plaza
  • Year and Date: 2015-09-26
  • Int'l Joint Research
• [Presentation] 不撹乱試料を用いたすべり面強度の温度依存性検証 (2015)
  • Author(s): 柴崎達也, 松浦純生，岡本隆，長谷川陽一
  • Organizer: 第54回日本地すべり学会研究発表会講演集
  • Place of Presentation: 山形テルサ
  • Year and Date: 2015-08-25
• [Presentation] Temperature-dependent residual shear strength characteristics of smectite-rich landslide soils (2015)
  • Author(s): Shibasaki T., Matsuura S., and Okamoto T.
  • Organizer: European Geoscience Union
  • Place of Presentation: Austria Center Vienna
  • Year and Date: 2015-04-13
  • Int'l Joint Research
• [Presentation] スメクタイトに富む粘土の残留強度の温度依存性とせん断速度との関係 (2014)
  • Author(s): 柴崎達也, 松浦純生，長谷川陽一
  • Organizer: 第53回日本地すべり学会研究発表会講演集
  • Place of Presentation: つくば国際会議場
  • Year and Date: 2014-08-19 – 2014-08-22