A method to predict sediment transport processes in drainage basins for sediment management

一种预测流域泥沙输送过程以进行泥沙管理的方法

• 批准号: 16360247
• 负责人: EGASHIRA Shinji
• 金额: $ 6.4万
• 依托单位: Ritsumeikan University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2004
• 资助国家: 日本
• 起止时间: 2004 至 2006
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-16360247/
• 关键词: Sediment runoff model; Sediment transport process; Rain fall runoff model; Landslide; Debris flow; Sedimentation; River bed variation; Impact of dam on sediment runoff process; Sediment management; 河床変動

A method which is composed of sub-models such as rainfall runoff, water flow, sediment transport and bed variation is proposed for evaluating sediment transport process in river basins and is tested for its validity and applicability. Especially, it is applied to investigate the sediment runoff from mountain areas and the associated bed evolution of alluvial reach in Takatoki river basin where a dam is planning to construct for flood control, supposing an occurrence of a plan size rainfall event with numerous landslides. Numerical computations were conducted for three cases: no impact of the dam on sediment transport process (Case 1), performances of flood control to reduce flow discharge with the dam (Case 2) and no performances of flood control but with the dam (Case 3). In cases 2 and 3, it is supposed that all sediment inflowing into the reservoir is caught in the storage area. Predicted results suggest that, in Case 1, a fine part of sediment produced by landslides in mountain area can be transported during a period of the flood to the alluvial reach and causes the bed variation although most of the coarse sediment remains in mountain reaches. After the flood, a very active sediment runoff from the mountain area to the flat region continues for long years, and causes river bed aggradation. The dam, which drains about 45 percent of the total basin area, catches a lot of sediment and suppresses the bed variation of alluvial reach during the flood as well as for long years after the event. In addition, sediment transport activities in mountain regions are impacted by reservoir sedimentation and decreases to suppress remarkably river bed aggradation of downstream flat area.

提出了一种由降雨径流、水流量、泥沙输送、河床变化等子模型组成的流域泥沙输送过程评价方法，并验证了其有效性和适用性。特别是，它适用于调查山区的泥沙径流以及高时河流域冲积河段的相关河床演化，该流域计划修建大坝防洪，假设发生计划规模的降雨事件并发生多次滑坡。数值计算分三种情况进行：大坝不影响输沙过程（情况1）、大坝防洪减流（情况2）、大坝不防洪（情况3） ）。在情况2和情况3中，假设流入水库的所有沉积物都被捕获在存储区域中。预测结果表明，在案例1中，山区滑坡产生的泥沙有一小部分可以在洪水期间被输送到冲积河段并引起河床变化，尽管大部分粗泥沙仍留在山区。洪水过后，泥沙径流非常活跃，从山区流向平原地区，持续多年，导致河床淤积。该大坝的排水量约占流域总面积的 45%，在洪水期间以及洪水过后的很长一段时间内，它捕获了大量沉积物并抑制了冲积河段的河床变化。此外，山区输沙活动受水库淤积影响而减少，下游平坦地区河床淤积受到明显抑制。

项目成果

Effect of debris flow discharge on equilibrium bed slope

泥石流排放对平衡床边坡的影响

• 发表时间: 2005
• 期刊: Proceedings of International Conference on River, Coastal and Estuarine Morphodynamics:RCEM-2005 Parker & Garcia(eds), Taylor & Francis Group, London
• 作者: Takahiro Itoh;Shinji Egashira
• 通讯作者: Shinji Egashira

Study on riven change and sediment transportation of Tan Chau reach in lower Mekong Riven

湄公河下游新洲河段裂痕变化及泥沙输送研究

• 发表时间: 2006
• 期刊: Proceedings of International Conference on Fluvial Hydraulics, River Flow(Lisbon, Portugal)
• 作者: Xuan Loc Luu;Shinji Egashira;Hiroshi Takebayashi
• 通讯作者: Hiroshi Takebayashi

Influence of dam construction on sediment runoff and bed variation during a plan size flood runoff

计划洪水径流期间大坝建设对泥沙径流及河床变化的影响

• 发表时间: 2006
• 期刊: Advances in River Engineering(in Japanese) Vol.12
• 作者: Komada;T.;T. Matsukawa;S. Egashira;K. Horie;N. Nishimoto
• 通讯作者: N. Nishimoto

Numerical and experimental studies on control functions of close type check dam against debris flow

密闭式淤地坝防泥石流控制作用数值与试验研究

• 发表时间: 2004
• 期刊: Proceedings of the 9th International Symposium on River Sedimentation, Yichang, China
• 作者: Shinji Egashira;Rabindra Osti;Takahiro Itoh
• 通讯作者: Takahiro Itoh

高時川流砂系における丹生ダムの影響

Nyu 水坝对 Takatoki 河流沙系统的影响

• 发表时间: 2005
• 期刊: 河川技術論文集 第11巻
• 作者: 藤田正治;里深好文;江頭進治;竹林 洋史・江頭 進治・永田 徹・桑島 信・加藤 陽平・伊藤 大祐;城戸 健太郎・松川 知三・吉栖 雅人・西本 直史・江頭 進治
• 通讯作者: 城戸 健太郎・松川 知三・吉栖 雅人・西本 直史・江頭 進治