Laboratory reproduction of weathering and deterioration of soft-rock slopes and its application to disaster mitigation.

2011 Fiscal Year Final Research Report

• Project/Area Number: 21246076
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Geotechnical engineering
• Research Institution: The University of Tokyo
• Principal Investigator: TOWHATA Ikuo 東京大学, 大学院・工学系研究科, 教授 (20155500)
• Co-Investigator(Kenkyū-buntansha): UCHIMURA Taro 東京大学, 大学院・工学系研究科, 准教授 (60292885) ; YAMADA Suguru 東京大学, 大学院・工学系研究科, 助教 (70451789)
• Project Period (FY): 2009 – 2011
• Keywords: 物理的風化 / 岩石 / 三軸圧縮試験 / ポイントローディング / 斜面崩壊 / 化学的風化 / S波伝播速度 / 凍結融解

Research Abstract

Physical weathering of rock material induces loss of rigidity and deterioration of strength. This process was first reproduced in a newly developed testing device in which water-submergence, freezing, and heating were repeated. This test was able to reproduce the said rigidity loss and strength deterioration. Second, field studies were made in slope instability areas in both Japan and Pakistan where slope disasters have been significant. By using the knowledge thus collected, a methodology was developed by which the temporal progress of weathering and deterioration is traced and the mitigation of slope disaster is initiated at a critical time when the instability is imminent.

Research Products

• [Journal Article] Geotechnical properties of weathered slopes in Muzaffarabad area after the 2005 Kashmir-Earthquake
  • Author(s): Aziz, M., Qureshi, M. U., Yamada, S., Towhata, I. and Khan. M. S.
  • Journal Title: Journal of Harbin Institute of Technology Volume: 16 Pages: 6-11
• [Presentation] Geotechnical risk assessment of highly weathered slopes using seismic refraction technique
  • Author(s): Qureshi, M. U., Towhata, I., Yamada, S., Aziz, M., and Aoyama, S.
  • Organizer: Proc. IS Kyoto 2009 Int. Symp
  • Place of Presentation: On Prediction and Simulation Methods for Geohazard Mitigation
• [Presentation] Water submergence effects on geotechnical properties of crushed mudstone
  • Author(s): Aziz, M., Towhata, I., Yamada, S., and Qureshi, M. U.
  • Organizer: Proc. IS Kyoto 2009 Int. Symp
  • Place of Presentation: On Prediction and Simulation Methods for Geohazard Mitigation
• [Presentation] Field Investigations of highly weathered slopes for geotechnical risk assessment
  • Author(s): Qureshi, M. U., Towhata, I., Yamada, S., Aziz, M., and Kubo, Y.
  • Organizer: Proc. 2^<nd> International Conference on New Developments in Soil Mechanics and Geotechnical Engineering
  • Place of Presentation: Near East University, Nicosia, North Cyprus
• [Presentation] Evaluation of mechanical parameters of weathered slopes by several insitu geotechnical surveys
  • Author(s): Yamada, S., Towhata, I., and Qureshi, Mohsin U.
  • Organizer: Proc. 10^<th> Asian Regional Conference on Soil Mechanics and Geotechnical Engineering
  • Place of Presentation: Hong Kong
• [Presentation] The effects of weathering on strength and deformation characteristics of soft rocks
  • Author(s): Qureshi, M. U., Towhata, I., Yamada, S., and Aziz, M.
  • Organizer: Proc. Int. Conf. Geotechnical Engineering
  • Place of Presentation: Lahore
• [Presentation] A simplified technique for slope stability assessment based on insitu S-wave velocity measurement
  • Author(s): Qureshi, Mohsin Usman, Yamada, S. and Towhata, I.
  • Organizer: International Symposium on The Earthquake-induced Landslides
  • Place of Presentation: ISEL-Kiryu