黄河下游中常洪水调控指标

从塑槽径流条件、水流动床阻力、河道整治、滩区及防洪等方面,论证了未来黄河下游主槽目标过流能力采用4 000m3/s左右的合理性,提出了黄河下游发生明显淤滩刷槽的临界流量。同时,根据不同量级洪水河道的冲淤特点,提出了小浪底水库控制下游流量、含沙量指标。即在目标主槽过流能力条件下,控制漫滩洪水流量不低于6 000m3/s,含沙量不大于250-300kg/m3;小漫滩洪水和非漫滩洪水,尽量按流量2 300-4 000m3/s、含沙量20-50kg/m3的水沙搭配控制,避免出现4 000-6 000m3/s8、00-2 300m3/s两个量级的洪水过程。

Regulation indexes of the medium flood in the Lower Yellow River

The rationality of flow-conveying ability of 4 000m~3/s in the main channel of the Lower Yellow River in the near future was discussed from the runoff condition of forming main channel,mobile-bed resistance,training works and flood control of the floodplain etc.The threshold of the flow discharge which can cause obvious silting in the floodplain and scouring in main channel was then proposed.Besides,the regulating indexes to the flow discharge and sediment concentration released from Xiaolangdi reservoir were proposed according to the sedimentation characteristics corresponding to different discharges in the Lower Yellow River.The indexes are that the over floodplain discharge should be more than 6 000 m~3/s and the concentration be less 300kg/m~3 under the objective main channel,for the light over floodplain flood and non-over floodplain flood the discharge and concentration should be regulated as 4 000m~3/s and 50 kg/m~3.The discharges ranges from 4 000 m~3/s to 6 000m~3/s and from 800 m~3/s to 2 300 m~3/s in the Lower Yellow River should be avoided.