曲条面引水渠首在阿韦滩渠首改造工程中的应用

摘要

在多沙河流上,泥沙淤积常会造成渠首引水设施的破坏,通过对阿韦滩渠首运行中发现的问题,结合当地工程实际,在原底栏栅式渠首基础上改造提出的一种新型引水渠首——曲条面引水渠首。该新型渠首利用弯道凸岸沉沙、凹岸引水的原理,对原底栏栅式引水渠首进行改扩建,在条形冲沙槽进水口前修建曲线形挡沙坎,采用曲面引水实现第一级水沙分离,凹岸表层较清的水流进入条形冲沙槽后,更清的水流入两侧的溢流槽,最终实现条形冲沙槽冲沙、溢流槽双向溢流面进水的第二级水沙分离。工程建成运行后,发现通过这两级的水沙分离过程,最终实现了其引水、排沙,水沙分离效果较好,值得推广应用。%A new intake headwork,called curvilinear surface intake headwork,is proposed in Arweitan reconstruction and extension project to solve the problem that the sediment deposition would cause the destruction in the water diversion facilities of sediment-laden rivers.Combined with the local engineering practices,the original bottom grating intake headwork is reconstructed and extended.A curved sand-control threshold is built at front of the intake of sand flushing channel,by which the water-sand separation in one-stage could be finished.After the lower sediment concentration flow in concave bank surface entered into the sand flushing channel,the upper-layer water with little sediment would overflow into the water diversion channel through its both sides,then the two-stage water-sand separation would be realized.After the project is completed,the sediment flushing effect of the new intake headwork is satisfied,and it is worth popularizing.