2013年汛前调水调沙期小浪底水库排沙特性分析

依据实测资料,从洪水过程、边界条件、水库运用等方面分析了2013年汛前调水调沙小浪底水库异重流排沙比偏高的原因如下:(1)三门峡水库蓄水量大,塑造的洪水过程流量大、历时长;(2)对接水位接近小浪底水库淤积三角洲顶点,使得三角洲顶坡段发生沿程冲刷及溯源冲刷;(3)在三门峡水库泄空期间,潼关断面流量较大历时较长。

Analysis on sediment releasing characteristics of Xiaolangdi Reservoir during period of water and sediment regulation before flood season of 2013

Based on the observed data，the causations of the higher ratio of sediment releasing by density current of Xiaolangdi Reservoir during the period of water and sediment regulation before flood season of 2013 are analyzed from the aspects of the flood process， boundary conditions， operation of reservoir， etc.， i.e.（1）the storage of Sanmenxia Reservoir is large， and then it can create a flood process with large discharge and long duration；（2）the butt-joint water level approaches the crest of the silted delta of Xiaolangdi Reservoir， which causes the stream-wise erosion and retrogressive erosion on the slope of the delta crest；（3）during the emptying period of Sanmenxia Reservoir， the discharge through Tongguan section is large with a long duration.