Embankment Failures and Slope Protection of Earth Dams during Flooding

洪水期间土坝的路堤溃决与护坡

基本信息

批准号：
08650584
负责人：
NARITA Kunitomo
金额：
$ 0.83万
依托单位：
Aichi Institute of Technology (A.I.T.)
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1996
资助国家：
日本
起止时间：
1996 至 1997
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08650584/
关键词：
Fill Dam Centrifuge Model Test Pore Water Pressure Seepage Failure Overflow Failure Slope Stabilization FEM Analysis

项目摘要

Centrifuge model tests were carried out in order to investigate the mechanism of seepage failures of earth dams caused by a rapid increase of reservoir water during flooding, to know which factor should be the main trigger of fracture and when and how it works in the process of overall failure of the embankment. Feasibility of realizing seepage failures in laboratory model tests is another important subject to be discussed for future studies on hydraulic fracturing in earth and rockfill dams. Tests were conducted on several model earth dams made under different compaction conditions to examine their influence on the development of pore-water pressure in the fill.Two distinct patterns were noticed in embankment failures caused by a rapid increase of reservoir water during flooding. One is in case of dry and poorly compacted fill where internal erosion (piping) due to seepage water flow through the dam body is predominant, though over-flow water initially causes a little damage to the downstream surface by gully erosion and contributes to a trigger of piping. The other is in case of fill in wet and/or highly compacted state before flooding, in which surface gully erosion due to over-flow of water extends in a constant rate to the upstream side with a little internal erosion. Measurement of pore-water pressure and FEM analysis on the model tests somewhat revealed the mechanism of these embankment failures, though further studies are required to give more precise and quantitative discussions. Concerning the slope protection work against flooding, a few model tests were carried out to investigate by what material and where and how it should be constructed to get more effective protection. Much discussion is still needed on this subject to apply it for actual design and construction of embankments.

进行离心模型测试是为了研究洪水过程中储层水的迅速增加而引起的土壤渗漏衰竭的机制，以了解哪个因素应该是断裂的主要触发因素，以及在洪水中的何时以及如何在其过程中起作用。路堤的总体故障。实现实验室模型测试中渗漏故障的可行性是为将来的关于地球和岩污水中液压压裂的研究讨论的重要主题。对在不同压实条件下制造的几个模型地球大坝进行了测试，以检查其对填充物中孔隙水压力发展的影响。在洪水期间，由于储层水的迅速增加，在路堤故障中发现了两种不同的模式。一个是在干燥且压实较差的情况下，由于渗流流经大坝体的内部侵蚀（管道）是主要的，尽管过量流水最初会因沟渠侵蚀对下游表面造成一点损害，并有助于触发器管道。另一个是在洪水之前填充湿和/或高度紧凑的状态的情况下，由于水过多而导致的表面沟渠侵蚀以恒定的速度延伸到上游侧，并稍有内部侵蚀。在某种程度上，对模型测试的孔隙水压和FEM分析的测量揭示了这些路堤故障的机制，尽管需要进一步的研究以进行更精确和定量的讨论。关于防止洪水的坡度保护工作，进行了一些模型测试，以调查什么材料，何处以及应如何构建以获得更有效的保护。仍然需要对此主题进行许多讨论，以将其应用于路堤的实际设计和建造。