Design and development of a riprap work having resistivity against overtopping flow on soil embankment.

土堤抗漫溢流抛石工程的设计与开发。

基本信息

批准号：
14560196
负责人：
MORII Toshihiro
金额：
$ 2.05万
依托单位：
Niigata University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2002
资助国家：
日本
起止时间：
2002 至 2003
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-14560196/
关键词：
Riprap work Overtopping flow Rockfill Head loss equation of flow Hydraulic mean radius of voids Laboratory water flume tests オーバートッピング(越流)流れの非線形水頭損失特性土砂の透水性捨石工(リップラップ工)水理学的安定性浸食メカニズム流れの水頭損失

项目摘要

The purpose of the Research Project Is to investigate hydraulic and mechanical properties of rockfill and to propose a design procedure of riprap work that effectively resist against overtopping flow on soil embankment. Rock has been advantageously employed in hydraulic structures such as rockfill dams, flow-through embankments, rubble weirs and riprap works. To predict a flow transmissibility of the rockfill structure, an accurate evaluation of head loss property of flow through rockfill is required. In the Research Project, a head loss equation of flow through rockfill that is applicable to a wide range of rock particle size is proposed. A quadratic equation is selected to describe the head loss property of flow through rock fill. Two nonlinear coefficients included in the equation are effectively determined as a function of a hydraulic mean radius of rockfill voids based on laboratory tests using river gravel 5 to 75 mm in diameter. It is shown that the head loss equation of flow determined can be well applied to predict the flow transmissibility of rockfill structures without any consideration of scale effect of flow. A numerical experiment is conducted to estimate an amount of laminar flow composing the flow through rockfill. The laminar flow is found to be negligible even in the flow through a small size structure constructed using small rock particles. A parameter estimation procedure that employs a simple genetic algorithm combined with FEM calculation is also developed to determine the nonlinear coefficients in the head loss equation from a stage-discharge rate data observed in the laboratory or in the field/ Investigations of the mechanical property of rockfill as well as of soil erosion in an underlying foundation that have been left behind this two-year project will be tackled successively by the Head Investigator.

该研究项目的目的是研究堆石料的水力和力学特性，并提出有效抵抗土堤漫溢流的抛石工程设计程序。岩石已被有利地应用于水工结构中，例如堆石坝、流通路堤、碎石堰和抛石工程。为了预测堆石结构的水流传输率，需要准确评估流过堆石的水头损失特性。在该研究项目中，提出了适用于各种岩石粒度的流经堆石的水头损失方程。选择二次方程来描述流经堆石的水头损失特性。根据使用直径为 5 至 75 mm 的河卵石进行的实验室测试，方程中包含的两个非线性系数被有效确定为堆石空隙水力平均半径的函数。结果表明，所确定的水流水头损失方程可以很好地应用于预测堆石料结构的水流传导率，而无需考虑水流的尺度效应。进行数值实验以估计构成通过堆石的流动的层流的量。研究发现，即使流经使用小岩石颗粒构建的小尺寸结构，层流也可以忽略不计。还开发了一种采用简单遗传算法与有限元计算相结合的参数估计程序，用于根据实验室或现场观察到的阶段流量数据确定水头损失方程中的非线性系数/堆石体力学特性的研究首席研究员将陆续解决这个为期两年的项目留下的基础土壤侵蚀问题。