| RETROGRESSIVE EROSION AND LONGITUDINAL PROFILE EVOLUTION IN NONCOHESIVE MATERIAL |
| |
| 作者姓名： | Lien-Kuang CHEN Su-Chin CHEN |
| |
| 作者单位： | Department of Soil and Water Conservation National Chung Hsing University Taichung Taiwan 402 China Dr.，Department of Soil and Water Conservation National Chung Hsing University Taichung Taiwan 402 China Prof. |
| |
| 摘 要： | 1 INTRODUCTION A headcut, which is an abrupt break in the slope of a channel bed, is often called a “knickpoint” or “scarp” in the study of rivers and waterways. A headcut tends to retreat upstream as water flows over it. As a headcut passes a cross s…
|
| 关 键 词： | 裂点 侵蚀作用 水土流失 河道 生态环境 |
| 收稿时间： | 2004-08 |
| 修稿时间： | 2005-09 |
RETROGRESSIVE EROSION AND LONGITUDINAL PROFILE EVOLUTION IN NONCOHESIVE MATERIAL |
| |
| Lien-Kuang CHEN Su-Chin CHEN.RETROGRESSIVE EROSION AND LONGITUDINAL PROFILE EVOLUTION IN NONCOHESIVE MATERIAL[J].International Journal of Sediment Research,2006,21(2):113-122. |
| |
| Authors: | Lien-Kuang CHEN Su-Chin CHEN |
| |
| Abstract: | Retrogressive erosion plays a significant role in soil erosion and in channel morphology evolution. Retrogressive erosion occurs and migrates when the flow conditions and/or channel bed slope change. This study investigates through a series of experiments, the migration behavior of retrogressive erosion and the longitudinal profile evolution of a channel consisting of noncohesive sediment. Experimental results indicate that retrogressive erosion can be categorized into two types, stepped and rotating. In stepped erosion a nearly parallel erosion surface migrates upstream at a constant speed. The migration speed in rotating erosion is a function of the square root of time. The experimental results reveal that the discharge does not affect the migration speed of stepped erosion. However, the migration speed of rotating erosion increases with rising discharge. The crucial difference between rotating and stepped erosion, i.e. the threshold value separating the two forms of erosion is a function of the initial channel bed lowering and critical water depth. A model of retrogressive erosion in a noncohessive channel is developed based on the experimental results. |
| |
| Keywords: | Headcuts Retrogressive erosion Knickpoint Stepped and rotating |
| 本文献已被 CNKI 维普 万方数据 等数据库收录！ |
