高扬程提水引黄灌区渠道水沙分布规律试验研究

Test Study on Distribution Regularity of Water and Sediment of Water Lifting in Irrigated Area of Yellow River Diversion

尊村引黄灌区是山西省一座大型多级高扬程提水灌溉工程,由于所引黄河水的泥沙含量较高,导致灌渠泥沙淤积问题十分严重,从而影响到了渠道的正常运行。为了掌握灌区渠道水沙分布规律,缓解渠道淤积问题,通过在尊村二干渠设立7个观测断面开展水沙监测,对渠道水流速度、含沙量及断面尺寸进行测定,并分析了渠道沿程流速和含沙量的变化情况与相互关系。结果表明,渠道的平均含沙量在0.7kg/m^3左右,沿程含沙量在0.63~0.82kg/m^3之间,总体变化不大,不同断面各个点流速的变化趋势大体相同,但变化规律不明显;右岸混凝土板衬砌,左岸未铺设,大多情况下右岸悬沙含量较左岸低;夏灌时的渠道含沙量大约是春灌时的2~3倍。研究结果可为灌区管理和节水减沙工作提供参考依据。

Zuncun Irrigated Area of Yellow River Diversion Project is a large water-lifting project for irrigation in Shanxi Province. Because of the high sediment concentration of the Yellow River, the sedimentation problem of irrigation canal is very serious, which affects the normal operation of the canal. In order to grasp the distribution regularity of water and sediment in the irrigation canals and ease the aggradation of canals, seven observation sections in Zuncun secondary trunk ditch were chosen to monitor water and sediment, measure and analyze flow velocity, sediment concentration, sand grading and section size. The change of flow velocity and sediment concentration along the canal was studied, and the re- lationship between them was analyzed. The results show that the average sediment concentration of the canal is about 0.7 kg/ma , the sediment concentration along the canal is in the range of 0.63 kg/ma and 0.82 kg/m3. Velocity of various points in different sections are approximately the same change trend, but the change rule is not obvious. The right bank of the irrigation canal is covered with concrete slabs. In most cases, the right bank has a lower sediment concentration than the left bank. The sediment concentration of summer irrigation is about 2-3 times that of spring irrigation. The study results provide a basis for irrigation district management and water-saving and sediment reduction.