三峡工程蓄水运用以来水库排沙效果  

On sediment diversion ratio after the impoundment of the Three Gorges Project

作　　者：陈桂亚[1,2] 袁晶 许全喜 

机构地区：[1]武汉大学水资源与水电工程科学国家重点实验室,湖北武汉430072 [2]长江水利委员会防汛抗旱指挥部办公室,湖北武汉430010 [3]长江水利委员会水文局,湖北武汉430010

出　　处：《水科学进展》2012年第3期355-362,共8页Advances in Water Science

基　　金：国家重点基础研究发展计划(973)资助项目(2012CB417001);水利部公益性行业科研专项经费资助项目(200901003)~~

摘　　要：针对三峡水库蓄水运用以来排沙比问题,在深入研究三峡水库不同蓄水运用阶段水库排沙效果的基础上,着重研究各年年内蓄水排沙过程,系统地分析水库排沙效果的影响因素。结果表明:库区河道特性、入库水沙条件以及坝前水位的高低是水库排沙比变化的主要影响因素。2003年6月～2010年12月,水库排沙比为26.1%。水库排沙主要集中在汛期5～10月,排沙比为29.0%。尤其是在洪峰期间,库区水流流速较大,水流挟沙能力强,进入水库的泥沙大部分能输移到坝前,水库排沙比较大,当入库流量大于30 000 m3/s时,水库最大排沙比可达81.0%。此外,随着汛期坝前水位的抬高,水库排沙效果有所减弱,尤其是粗颗粒泥沙的多少也很大程度上影响水库排沙效果,水流的挟沙能力随着水流流速的减小而减小,粗颗粒泥沙的排沙比随之发生较全沙更为明显的减小。This paper systematically studies the hydraulic factor and sediment transportation character in the reservoir area after the impoundment of the Three Gorges Reservoir, the influencing factor to the sediment diversion ratio of the TGP. The conclusion indicated that there are three important influencing factors to the sediment diversion ratio, one is the riverbed character of the reservoir area, the other is the flow and sediment condition, and the third is the water level before dam. From June 2003 to December 2010, the sediment diversion ratio is 26.1%. The sediment discharging centers from May to October each year, during which the sediment diversion ratio is about 29.0% , especially during the flood peak time, the velocity is large, and the flow has a strong sediment transportation ability, the sediment diversion ratio is high, when the inflow discharge is larger than 30 000 m^3/s, the highest sediment diversion ratio is 81.0%. Further more, with the rise up of the water level before dam, the sediment diversion ratio decreased, especially the capacity of coarse particle, to some extent, it affects the sediment diversion ratio, the sediment transport ability decreases with the decreasing of the flow velocity, accordingly, the sediment diversion ratio of the coarse particle decreases more evident than the total load with the decreasing of the flow velocity.

关 键 词：三峡工程 排沙效果 泥沙淤积 影响因素 

分 类 号：TV697.2[水利工程—水利水电工程]