2014 Fiscal Year Final Research Report
Micromechanics of granular flow with duality of particle and continuum in multi-scales
Project/Area Number |
25630201
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Research Category |
Grant-in-Aid for Challenging Exploratory Research
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Allocation Type | Multi-year Fund |
Research Field |
Geotechnical engineering
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Research Institution | Nagoya Institute of Technology |
Principal Investigator |
MAEDA Kenichi 名古屋工業大学, 工学(系)研究科(研究院), 教授 (50271648)
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Project Period (FY) |
2013-04-01 – 2015-03-31
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Keywords | 個別要素法 / 限界状態 / 応力鎖 / 粒子骨格構造 / 粒度変化 / 分級 / 逆グレーディング / 土石流 |
Outline of Final Research Achievements |
Slope disasters inducing stony-type flow are occurring more frequently due to global climate changes, but the mechanisms of granular flow have not been thoroughly explained. The mechanism of dry granular flow was examined in micro and macro views. Flow behaviors of dry granular materials on a slope were examined using PIV image analysis and a discrete element method. Relationships exist between macro and micro behaviors during phenomena such as velocity distributions in depth stratification and uplifts of large particles that change flow grades. Stress chains are transmission paths of contact forces. The distribution of the averaged coordination number was found to correspond to the velocity distribution. This stratification could be explained by the state parameter, a relative variable dependent on void ratio, mean normal stress, and critical state. Moreover, the stress chains formed from the riverbed concentrated the larger particles and pushed them upwards towards the flow surface.
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Free Research Field |
地盤工学
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