北京市大中型水库下游河道行洪能力分析——以怀柔水库为例

Analysis on Flood Discharge Capacity of Downstream River of Large and Medium-sized Reservoirs in Beijing——Taking Huairou Reservoir as an Example

大中型水库在发生超标准洪水时,下游河道及两岸保护区会面临巨大的洪水风险。为保障河道行洪安全,需要对河道行洪能力进行分析,确定其过流能力及阻水建筑物对行洪的影响。以怀柔水库下游主河道怀河为例,利用一二维水动力模型,阐述了如何构建数值模型,设置合适的模拟方案并分析方案结果。结果显示了怀河的具体行洪能力,并针对怀河上阻水建筑物的影响做了进一步的研究,结果表明阻水建筑物会对河道水位及漫堤后的淹没范围造成不利影响,壅高水位并增大淹没面积,为保障行洪安全应尽量减少阻水建筑物,避免不利影响。

When the over-standard flood occurs in large and medium-sized reservoirs,the downstream river courses and the protection areas on both banks will face huge flood risks. In order to ensure the safety of flood discharge in the river courses,it is necessary to analyze the flood discharge capacity of the river courses,determine their discharge capacity and the impact of water blocking structures on the flood discharge. This paper takes the main river course at the downstream of Huairou Reservoir as an example,uses 1D and 2D coupling hydrodynamic model and explains how to build a numerical model,set up an appropriate simulation scheme and analyze the scheme results. The results show the specific flood discharge capacity of Huaihe River,and further study is made on the impact of water blocking structures on Huaihe River.The results show that water blocking structures will have adverse effects on the river water level and the flooded area after overtopping the embankment. The water level will be raised and the flooded area will be increased. In order to ensure the safety of flood discharge,water blocking structures should be reduced as much as possible to avoid adverse effects.