三峡水库淤积排沙及河型转化规律  

Sedimentation and Sediment Delivery and River Pattern Conversionin the Three Gorges Reservoir

作　　者：金中武[1] 任实 吴华莉[1] 朱帅[1] 王玉璇 李秋荔 JIN Zhong-wu;REN Shi;WU Hua-li;ZHU Shuai;WANG Yu-xuan;LI Qiu-li(River Department, Yangtze River Scientific Research Institute, Wuhan 430010, China;Department of Projects Management, China Three Gorges Corporation, Yichang 443133, China)

机构地区：[1]长江科学院河流研究所,武汉430010 [2]中国长江三峡集团有限公司枢纽管理局,湖北宜昌443133

出　　处：《长江科学院院报》2020年第10期9-15,27,共8页Journal of Changjiang River Scientific Research Institute

基　　金：国家重点研发计划项目(2016YFC0502201);三峡水库科学调度关键技术第二阶段研究项目(SXSN/4277);国家自然科学基金项目(51779015,51809013);湖北省人民政府智力成果采购项目(HBZZ-2019-18)。

摘　　要：三峡水库泥沙排沙在其论证和运行阶段一直是关注的热点问题。根据上游来水来沙、实测固定断面和河床质地取样等资料,分析了三峡水库运用以来进出库水沙变化、总体淤积和排沙规律、沿程淤积规律、河型转化规律等,并将初步设计论证研究成果与其他成果进行了对比分析。研究成果表明:三峡水库运用后,入库年径流量与建库前变化不大,但年输沙量锐减60%,来沙减少的趋势仍将持续;三峡水库平均年库容损失率为0.3%,在世界范围内是非常低的,可确保水库长期使用;三峡水库的年淤积量与入库沙量基本呈线性关系,汛期蓄水位越高则其斜率越大;三峡库尾河段总体呈冲刷状态,泥沙主要淤积在常年回水区,尤其在河道开阔断面;部分分汊河道发生了河型转化,淤积后河道总体朝单一、归顺方向发展。研究成果可为三峡水库运行管理和研究提供支撑,也为同类型水库决策提供参考。Sedimentation and sediment delivery in the Three Gorges Reservoir(TGR)has always been a hot issue during its demonstration and operation.In this study,long-term series field measured hydrological and terrain data before and after the TGR’s impoundment are used to investigate the trend of runoff and sediment load transport into the TGR.The effect of sedimentation on the TGR is discussed.The result demonstrates that despite rare changes in annual runoff,the total amount of sediment load transport into the TGR shows a significant reducing trend(by 60%)after the impoundment of the TGR.Analysis of the field data shows that the average sediment delivery ratio of the TGR is 24%during 2003-2018 and the annual loss in storage capacity is about 0.3%.Annual sedimentation is in a linear relation with incoming sediment,and the slope of the relation is larger when water level gets higher in flood season.Sediment mainly deposits in river reaches with wide cross sections,especially in the permanent backwater area where the flow velocity is relatively small.In some branching reaches,the river pattern develops towards unification.It is expected that this study will help optimizing the TGR operations and improving its comprehensive function.

关 键 词：泥沙淤积 排沙率 河型转化 入库沙量 三峡水库 

分 类 号：TV14[水利工程—水力学及河流动力学]