Empirical model for assessing dynamic susceptibility of post-earthquake debris flows | |
Language | 英语 |
Hu, Kaiheng1,2![]() ![]() ![]() | |
2019 | |
Source Publication | Debris-Flow Hazards Mitigation: Mechanics, Monitoring, Modeling, and Assessment - Proceedings of the 7th International Conference on Debris-Flow Hazards Mitigation |
Author of Source | Access Limited Construction ; Association of Environmental and Engineering Geologists ; BGC Engineering Inc. ; et al. ; Geobrugg North America ; KANE Geotech Inc. |
Pages | 973-980 |
meeting | 7th International Conference on Debris-Flow Hazards Mitigation: Mechanics, Monitoring, Modeling, and Assessment |
Conference Date | June 10, 2019 - June 13, 2019 |
Conference Place | Golden, CO |
Country | United states |
Contribution Rank | 1 |
Abstract | Particle size segregation is a common feature in debris-flow deposits and is assumed to develop in a similar way as in dry granular flows where fluid forces are neglected. Solid-fluid coupling however is a defining feature of debris flows and fluid forces must therefore be accounted for in modelling for the segregation that develops therein. This paper presents a numerical investigation of the mechanisms of segregation under the influence of fluid forces. For this, a segment of a fully submerged bi-disperse steady granular flow is simulated using the CFD-DEM method. The solid-fluid interactions come in the form of buoyancy and fluid drag force. It is found that the presence of the fluid generally retards the rate and quality of segregation primarily by promoting the formation of a plug flow in the stream-wise velocity profile. The plug flow region forms at the free surface where it significantly reduces or zeroes out the shear rates thus inhibiting the main mechanisms of segregation, i.e. kinetic sieving and squeeze expulsion, to take place. It is inferred that the rapid shearing that occurs near the base promotes segregation but is unable to proceed towards the free surface due to the presence of the plug flow region that serves as a barrier. The quality of submerged segregation improves at lower angles where the plug flow region is minimized and the usual parabolic shear profile develops. © 2019 Debris-Flow Hazards Mitigation: Mechanics, Monitoring, Modeling, and Assessment - Proceedings of the 7th International Conference on Debris-Flow Hazards Mitigation. All rights reserved. |
Keyword | Buoyancy Confined flow Debris Drag Granular materials Hazards Particle size Segregation (metallography) Shear flow Surface segregation |
DOI | 10.25676/11124/173119 |
ISBN | 9780578510828 |
URL | 查看原文 |
Indexed By | EI |
Accession number | Accession number;20200408088117 |
Citation statistics | |
Document Type | 会议论文 |
Identifier | http://ir.imde.ac.cn/handle/131551/33788 |
Collection | 山地灾害与地表过程重点实验室 |
Corresponding Author | Hu, Kaiheng |
Affiliation | 1.Key Laboratory of Mountain Hazards and Earth Surface Processes, Chinese Academy of Sciences, Chengdu, Sichuan; 610041, China; 2.Institute of Mountain Hazards and Environment, Chinese Academy of Sciences and Ministry of Water Conservancy, Chengdu, Sichuan; 610041, China; 3.University of Chinese Academy of Sciences, Beijing; 100049, China |
First Author Affilication | 中国科学院水利部成都山地灾害与环境研究所 |
Corresponding Author Affilication | 中国科学院水利部成都山地灾害与环境研究所 |
Recommended Citation GB/T 7714 | Hu, Kaiheng,Wang, Zhang,Chen, Cheng,et al. Empirical model for assessing dynamic susceptibility of post-earthquake debris flows[C]//Access Limited Construction, Association of Environmental and Engineering Geologists, BGC Engineering Inc., et al., Geobrugg North America, KANE Geotech Inc.,2019:973-980. |
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06-08_Hu.pdf(6243KB) | 会议论文 | 开放获取 | CC BY-NC-SA | View Application Full Text |
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