小浪底水库运用以来库区淤积形态分析

Analysis of Deposition Morphology of Xiaolangdi Reservoir since Operation

分析了小浪底水库运用以来库区的淤积形态,结果表明:水库非汛期蓄水拦沙,淤积形态变化不大;调水调沙期间及汛期发生洪水时,淤积形态受水沙条件、边界条件及水库运用方式的影响而调整,截至2010年汛后,小浪底全库区断面法计算淤积量为28.225亿m3,其中干、支流淤积量分别为22.395亿m3、5.830亿m3,支流淤积量占总淤积量的20.7%;库区干流呈三角洲淤积形态,并逐步向下游推进,支流口门淤积较为平整,支流河床纵剖面沿流向呈现一定的坡降;畛水沟口形成了高10.5 m的拦门沙坎,建议开展畛水拦门沙坎的防治研究。

The paper studied the deposition morphology of Xiaolangdi Reservoir since operation.The results indicate that in non-flood season,the reservoir is in impoundment and sediment retention operation,and deposition morphology has little change.During regulated discharge regime and flood season of the Yellow River,affected by water and sediment conditions,boundary conditions and reservoir operation mode,deposition morphology changes constantly.By post-flood season of 2010,the amount of sediment in Xiaolangdi Reservoir has already reached 2.822 5 billion m3.In which,the amount of sediment in the stem and tributaries are 2.239 5 billion m3 and 0.583 0 billion m3 respectively.The amount of sediment in tributaries occupies 20.7% of the total.The stem deposition morphology is in the form of delta and moves downstream gradually.Deposition surface in tributary mouth is leveling,and along flow direction,tributary bed profiles present a certain gradient.There is 10.5 m channel-mouth bar in the tributary of Zhenshui.We suggest conducting research on prevention and treatment of channel-mouth bar of tributary Zhenshui.