摘要
随着金沙江下游梯级水库陆续建设和投入运用,坝下游的水沙过程明显改变并影响通航条件。本文提出了水沙过程非恒定变化分析方法,分析了向家坝枢纽坝下水位、流量和含沙量非恒定变化特性及其对通航条件的影响。结果表明,向家坝枢纽运用后坝下水沙变化的非恒定强度较大,水位变化的变异系数可以达到0.10～0.12,流量变化变异系数可以达到0.20～0.40,虽然出库含沙量显著减小,但含沙量变异系数最大可以达到约1.0。向家坝水文站标准化年平均水位和流量约为1.0左右,向家坝枢纽坝下山区河道的通航条件总体上是稳定的,水库运用削减洪峰和增大枯水流量有利于改善坝下河道的通航条件,但水电站日调节和水库蓄水,以及泄洪增大流量和水位的非恒定性,对坝下河道的通航条件有一定不利影响。
With the construction and application of cascade reservoirs in the Lower Jinsha River,the water and sediment processes downstream of the reservoirs are obviously changing and affecting navigation conditions. The analysis method of water and sediment unsteady process is proposed,and the unsteady characteristics of water level,discharge and sediment concentration downstream of Xiangjiaba reservoir and its influence on navigation conditions are analyzed. The results show that the variation coefficient of water level can reach 0.10~0.12,and the variation coefficient of discharge can be 0.20~0.40. Although the sediment concentration decreased significantly,the variation coefficient of sediment concentration could reach about 1.0. The annual average normalized water level and discharge in Xiangjiaba hydrologic station is about 1.0,and the navigation conditions of the montanic river channel downstream of Xiangjiaba reservoir are generally stable.It is beneficial to reduce the flood peak and increase low discharge to the navigation conditions of the river channel downstream the dam,but the daily regulation of the hydropower station,the reservoir water storage and the flood discharge increase the inconstancy of the flow and water level,which have some adverse effects on the navigable conditions.
作者
陈绪坚
CHEN Xujian(State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin,Laboratory of Hydraulics and Sediment Science and River Training of Ministry of Water Resources,China Institute of Water Resources and Hydropower Research,Beijing 100048,China)
出处
《水利学报》
EI
CSCD
北大核心
2019年第2期218-224,共7页
Journal of Hydraulic Engineering
基金
国家重点研发计划项目(2016YFC0402104)
关键词
金沙江下游
梯级水库
水沙过程
非恒定变化
通航条件
Lower Jinsha River
cascade reservoirs
water and sediment process
unsteady change
navigation conditions
