Slope failure mechanism for crushable volcanic soi I at snowy cold region and its modeling
Grant-in-Aid for Scientific Research (B)
|Allocation Type||Single-year Grants |
Natural disaster science
|Research Institution||Hokkaido University |
MIURA Seiichi Hokkaido Univ., Grad.School of Eng., Professor, 大学院工学研究科, 教授 (00091504)
AKAGAWA Satoshi Hokkaido Univ., Grad.School of Eng., Professor, 大学院工学研究科, 特任教授 (90360932)
ISHIKAWA Tatsuya Hokkaido Univ., Grad.School of Eng., Associate Professor, 大学院工学研究科, 助教授 (60359479)
YOKOHAMA Shoji Hokkaido Univ., Grad.School of Eng., Research Associate, 大学院工学研究科, 助手 (50299731)
KAWAMURA Shima Muroran Inst.of Tech., Faculty of Eng., Assistant Professor, 工学部, 講師 (90258707)
|Project Period (FY)
2004 – 2006
Completed (Fiscal Year 2006)
|Budget Amount *help
¥13,400,000 (Direct Cost: ¥13,400,000)
Fiscal Year 2006: ¥1,700,000 (Direct Cost: ¥1,700,000)
Fiscal Year 2005: ¥2,000,000 (Direct Cost: ¥2,000,000)
Fiscal Year 2004: ¥9,700,000 (Direct Cost: ¥9,700,000)
|Keywords||Cold Region / Volcanic Soil / Freeze-Thaw Sequential Action / Slope Failure / Particle Breakage / Ground Disaster Prevention / Laboratory test / Numerical Analysis|
Based on the experimental and numerical studies of slope stability of crushable soils, the following conclusions are obtained:
1.Effect of freeze-thaw sequence on static mechanical behavior of volcanic soil
(1)Particle breakage of volcanic coarse-grained soil significantly occurs due to the repetition of freeze-thaw sequence. The particle breakage affects strongly on static strength and rigidity of volcanic soil.
(2)Volcanic soil subjected to freeze-thaw sequences may produce a remarkable crushability at low confining pressure level. This fact suggests that deterioration in the stability of slope near the surface is significant on snowy cold region.
2.Effect of freeze-thaw sequence on dynamic mechanical behavior of volcanic soil
(1)Shear modulus of volcanic coarse-grained soil decreases due to freeze-thaw sequences. On the other hand, freeze-thaw action may less affect hysteresis damping ratio.
(2)Liquefaction resistance of volcanic soil decreased due to freeze-thaw sequences. This fact may
attribute the reduction of the liquefaction resistance to the increase in finer content induced by particle breakage during freeze-thaw sequences.
3.Rainfall-induced slope collapse for crushable volcanic soil and its evaluation
(1)From the results of model tests, it is found that excess pore water pressure and saturation degree play a key role in the slope failure induced by rainfall.
(2)Depth and shape of impermeable layer in the slope are critical to estimate the stability of slope.
4.Numerical analysis for rainfall-induced slope failure for crushable volcanic soil
(1)A series of numerical analysis by DEM showed that proposed small void elements between soil particles, which are able to expand in accordance with temperature depression, can simulate the mechanical freeze-thaw performance of granular materials.
(2)Discontinuous Deformation Analysis (DDA) could explain the slope failure mechanism if rainfall and dilatancy effects on volcanic soil are estimated appropriately into analysis algorithm. Less
Report (4 results)
Research Products (25 results)