南水北调中线工程总干渠水面线研究

南水北调中线工程总干渠设计需要3条特征水面线,即:设计水面线、设计流量水面线、加大流量水面线.合理地确定特征水面线,对于总干渠设计、工程投资及安全运行影响重大.就建立总干渠数字模型的必要性与可能性进行了研究,在数字模型上进行设计流量水面线和加大流量水面线的计算,并就过水建筑物的壅水特性及桥墩、渠道变截面对水面线的影响进行了分析.还就总干渠在运行过程中如糙率、建筑物渐变段水头损失系数发生变化时,可能对水面线的影响作了敏感性分析.

Research on water surface profile of artery canal of middle route project of South-to-North Water Transfer

The design of the trunk canal of the middle-route project of South-toNorth Water Transfer needs three characteristic water surface profiles: design water surface profile,water surface profile for design discharge,water surface profile for increased discharge.The reasonable determination of these characteristic water surface profiles is of great significance to the design,project investment and safe operation of the trunk canal.This paper makes a research on the necessity and possibility of establishing a numerical model to calculate the water surface profiles for the design discharge and the increased discharge,analyze the influences of overflow structures' backwater behavior,bridge piers and varied canal cross-sections on water surface profiles,and conduct the sensitivity analysis of possible influences of changes in the trunk canal's roughness and in head loss coefficient of structures' transition section on water surface profiles.