Japan Geoscience Union Meeting 2015

Presentation information


Symbol H (Human Geosciences) » H-DS Disaster geosciences

[H-DS25] Geohazards in humid, tectonically active countries and their precursors

Wed. May 27, 2015 12:00 PM - 12:45 PM 101A (1F)

Convener:*Masahiro Chigira(Disaster Prevention Research Institute, Kyoto University), Satoru Kojima(Department of Civil Engineering, Gifu University), Hiroshi YAGI(Faculty of Art, Science and Education, Yamagata University), Taro Uchida(National Institute for Land and Infrastructure Management), Chair:Tomoyuki Iida(防災科学技術研究所), Hiroshi Kobayashi(Aero Asahi Corporation)

12:24 PM - 12:27 PM

[HDS25-P10] The mechanism of strain rate strengthening during landslide

3-min talk in an oral session

*Kotaro TAKE1, Arito SAKAGUCHI1, Shinji SATAKE2 (1.Yamaguchi Univ., 2.Fukken co.,ltd.)

Keywords:landslide, strain rate strengthening

Many landslides slip relatively slowly without catastrophic failure. The slip events happen when sporadic hard rainfall. Monitoring and disaster prevention measures are carried out in some landslide area. These monitoring records must be useful to elucidate landslide mechanism. This study shows detailed slip behaviors at landslide by monitoring records of landslide.
The study area is located in Hiroshima, southwestern Japan. The talus sediments are overlained by the mudstones of the basement rocks. The mudstones include the basal slip fault of the landslide of several centimeters in width. In situ strain and groundwater level were observed in five borehole sites. Ground surface movements were observed by extensometers. The groundwater level increased immediately after beginning of the rainfall, and which trigger the landslide. The acceleration rate of the landslide, decreased with slip velocity. This demonstrates strain rate strengthening.