三峡水库汛期排沙规律研究

Sediment discharge characteristics of the Three Gorges Reservoir during flood seasons

汛期排沙是控制泥沙淤积的重要途径。本文通过概化理论推导分析了影响三峡水库汛期排沙的主要因素,依据实测水沙资料建立了三峡水库汛期排沙比经验公式,探讨了汛期优化调度下的泥沙淤积风险。研究结果表明:三峡水库蓄水以来汛期来沙占全年来沙的90.5%以上,且主要集中于场次洪水过程;建立了汛期排沙比经验公式,三峡汛期排沙比受流量和水位的双重影响,与代表进出库流量和坝前水位的综合影响因子呈较好的反比关系;汛期可采用“大水低位、小水高位”的运行方式提高综合效益。本研究能够为控制三峡水库泥沙淤积、优化汛期运行方式等提供重要参考。

The sediment discharge during flood seasons is important to reservoir sedimentation management.By generalization theory deduction,this article analyzed the main factors affecting sediment discharge during flood seasons of the Three Gorges Reservoir.Based on measured water and sediment data,an empirical formula for the sediment discharge ratio during flood seasons of the Three Gorges Reservoir was established,and the risk of sediment accumulation under optimized flood seasons scheduling was discussed.Results showed that the incoming sediment of the Three Gorges Reservoir in flood seasons accounted for more than 90.5%of the annual incoming sediment,which was mainly concentrated during flood.The empirical formula for sediment discharge ratio during flood seasons was established.The sediment discharge ratio was influenced by both flow rate and water level,and had a good inverse relationship with the comprehensive influencing factors represented by the inflow and outflow of the reservoir and the water level in front of the dam.During flood seasons,the operation mode of“high inflow with low water level,low inflow with high water level”could be adopted to improve comprehensive benefits.This research could provide reference for sedimentation management and optimal operation of the Three Gorges Reservoir.