三峡水库有效库容监测分析与长期保持对策建议  

Monitoring and evaluation of effective storage capacity of the Three Gorges Reservoir and strategic suggestions for its long-term maintenance

作　　者：胡春宏[1] 方春明[1] 关见朝[1] Hu Chunhong;Fang Chunming;Guan Jianchao

机构地区：[1]中国水利水电科学研究院,北京100048

出　　处：《中国水利》2024年第22期17-25,共9页China Water Resources

基　　金：中国长江三峡集团有限公司科研项目(0704229);三峡后续工作项目(12630100100023J046)。

摘　　要：2003年三峡水库蓄水运用至今已逾20年,通过持续的水文泥沙监测和跟踪分析,三峡水库泥沙问题研究获得很多新认识和新成果。实测资料分析表明:2003—2023年三峡水库干流库区累积淤积泥沙量18.014亿m^(3);库区干、支流有效库容内淤积泥沙量1.6亿m^(3),占总有效库容的0.72%。三峡水库纵向淤积分布呈三角洲形态,2012年以后淤积三角洲进入稳定淤积发展阶段,在未来较长时间内,淤积三角洲段和三角洲以下至大坝段淤积量占比将维持在2/3和1/3左右。有效库容淤积主要发生在三角洲的上段,当边滩高程发展到高于汛限水位后,少量宽断面将带来较快的有效库容损失,应将其作为减少有效库容淤积的主要库段;洪水来沙量大时,应尽量控制三角洲滩面不被整体淹没,坝前水位150 m是控制水库有效库容淤积的关键约束指标。从2012年开始,三峡水库开展了汛期沙峰排沙调度试验和消落期库尾减淤调度试验,对减少有效库容淤积具有良好效果。研究表明,三峡水库采取优化调度措施,可以有效降低水库有效库容的淤积损失,这些措施主要包括:优化汛期水位动态变化、汛期沙峰排沙调度、消落期库尾减淤调度、减淤疏浚工程措施等。提出了三峡水库减淤目标库段和关键控制指标及措施建议,以期为三峡水库库容安全提供科技支撑。The Three Gorges Reservoir has been in operation for over 20 years since its impoundment in 2003.Through continuous hydrological and sediment monitoring and tracking analysis,the study of sedimentation has achieved fruitful results.The actual measured data shows that the sediment accumulation in the mainstream reservoir area of the Three Gorges Reservoir had reached 1.8014 billion cubic meters from 2003 to 2023.The sediment accumulated in the effective storage capacity of the main and tributaries in the reservoir area was 160 million cubic meters,accounting for 0.72% of the total.The vertical sedimentation distribution of the reservoir was in the form of a delta.After 2012,the sedimentation delta entered a stable development stage.In the long term,the proportion of sedimentation in the delta section and below to the dam section will remain at around 2/3 and 1/3 respectively.Effective storage capacity siltation mainly occurs in the upper section of the delta.When the elevation of the beach reaches a level higher than the flood control water level,a small amount of wide cross-section will cause rapid loss of effective storage capacity,which should be regarded as the main reservoir section to reduce effective storage capacity.When the flood brings a large amount of sand,overall submergence of the delta beach surface should be avoided.The water level of 150 meters in front of the dam is a key constraint indicator for controlling the effective storage capacity of the reservoir.Since 2012,the Three Gorges Reservoir has carried out flood season sediment peak discharge scheduling and drawdown period sediment reduction scheduling experiments at the tail of the reservoir,in order to reduce sediment.It shows that adopting optimized scheduling shall effectively reduce loss caused by sedimentation.These measures mainly include optimizing dynamic changes of water level and scheduling sand peak discharge during the flood season,reducing sedimentation at the tail of the reservoir during the drawdown period and dredging.Measures

关 键 词：三峡水库 水库泥沙淤积 有效库容 长期保持 减淤措施 

分 类 号：TV697[水利工程—水利水电工程] TV145