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言語
英語
著者
佐藤 真理 環境共生科学科
内容記述(抄録等)
Seepage flow in unsaturated soil cannot be accurately calculated or measured using existing theories, as they consider several assumptions, and associated simulations are conducted under ideal conditions. Exact values such as velocity and pressure inside the unsaturated ground are not obvious that are often estimated by the seepage flow analysis. Those estimated values are not often corresponded to the measured values well. This study aimed to re-evaluate the conditions that well-known theories are established without any failures and aim to reduce the inconsistency for numerical analysis. Concretely, it develops a simple method to judge the inconsistency of well-known theories on geotechnical engineering in unsaturated soil by utilizing the fundamental magnitude relations of several properties and velocity terms in Bernoulli’s principle. As a result, consistent and inconsistent conditions are classified, although it is estimated that continuous seepage ranges close to the piezometric head conservation equation: h = z + ψ. The classification by this judgement is contributed to the estimation of the ground seepage condition using the combination of pressure head and hydraulic head difference in practical sites. Moreover, the inconsistency can be solved by assuming the local hydraulic gradient distributions. The hydraulic gradient modification is proposed by installing tentative seepage length and tentative hydraulic head for flow analysis. Finally, the local hydraulic gradient led by the proposed equations is calculated with the Mualem–van Genuchten model; the calculation results show the modified local hydraulic gradient is valid and applicable. Future works include discretization and analytical method. The criterion can immediately judge whether ground conditions and modification methods can be used for a more accurate seepage analysis in unsaturated soil.
主題
Unsaturated
Judgement criteria
Bernoulli’s principle
Numerical analysis
Water content
掲載誌名
Arabian Journal of Geosciences
13
16
開始ページ
Article number: 801
ISSN
1866-7511
ISSN(Online)
1866-7538
発行日
2020-08-15
DOI
出版者
Saudi Society for Geosciences, Springer Nature
資料タイプ
学術雑誌論文
業績ID
39536
部局
生物資源科学部
備考
This article is licensed under a Creative Commons Attribution 4.0 International License.