Development of Integrated Sediment Delivery Systems throughout a River System

整个河流系统综合输沙系统的开发

基本信息

批准号：
11558048
负责人：
TAKAHASHI Tamotsu
金额：
$ 8.58万
依托单位：
KYOTO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2001
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-11558048/
关键词：
Sediment runoff Reservoir sedimentation Open-type sabo dam Field observation Prediction model Sediment mixture 貯水池排砂

项目摘要

This research aims to develop the methods 1) to predict the sediment delivery along the river system by giving only rainfall, sediment characteristics and topographic conditions, 2) to effectively control debris flow using the open type sabo dams, and 3) to flush sediment from a comparatively large reservoir.Concerning with the theme 1), a numerical simulation method that combines the kinematic wave flood runoff analysis with the sediment entraining and detraining analysis is developed. A special contrivance to take the sediment supply from bare slopes is included. This method is applied to explain the sediment runoff within the watershed of Takase reservoir and the sediment disasters triggered by a severe rainfall in Venezuela, and it is proved valid and useful to examine the efficiencies of various countermeasures.As for the theme 2), a stochastic model for the clogging of grid-type dam by boulders contained in debris flow is introduced. This model is combined with a particle segregation process model to numerically simulate the debris flow control by grid-type sabo dam. This method is proved valid by experiments.Concerning with the theme 3), a new system to flush sediment from reservoir is invented. A small dam is constructed inside of the reservoir near the upstream end, and the yielded sediment accumulates only upstream of this sub-dam. During flood recession period, water and sediment stored upstream of the sub-dam are emptied through a bypass tunnel to the rfirer reach downstream of the main dam. If erosion of the delta deposit accumulated the backside of sub-dam is not sufficient, reverse flow from the main reservoir is introduced to scour the deposit. The feasibility of this system is examined by both laboratory experiments and numerical simulations, and it isproved feasible.

本研究旨在开发以下方法：1）通过仅给出降雨量、沉积物特征和地形条件来预测沿河流系统的沉积物输送量，2）利用开放式萨博坝有效控制泥石流，以及3）冲走沉积物针对1）主题，提出了运动波洪水径流分析与夹泄泥沙分析相结合的数值模拟方法。其中包括一种从裸露斜坡获取沉积物供应的特殊装置。该方法应用于解释高濑水库流域内的泥沙径流以及委内瑞拉强降雨引发的泥沙灾害，验证了该方法的有效性和实用性，检验了各种对策的有效性。对于主题2），介绍了泥石流中的巨石堵塞栅格坝的随机模型。该模型与颗粒离析过程模型相结合，对网格型萨博坝泥石流治理进行数值模拟。实验证明该方法是有效的。针对主题3），发明了一种新的水库沉积物冲刷系统。水库上游端附近建有一座小坝，产生的泥沙仅积聚在该子坝的上游。在洪水退潮期间，子坝上游储存的水和沉积物通过旁路隧道排空至主坝下游的引火河段。如果子坝背面堆积的三角洲沉积物侵蚀不充分，则引入主水库的逆流冲刷沉积物。通过室内实验和数值模拟验证了该系统的可行性，证明是可行的。