黄河艾山以下河道挖泥疏浚工程断面设计初步研究

Preliminary Study of the Section Design of Dredging Warping Downstream of Aishan on the Yellow River

根据艾山以下河道的冲淤特性确定了挖泥疏浚的设计流量；依据实测资料建立了河槽糙率与流速的关系，并以此确定河床的糙率。从输沙能力的角度分析了断面形态对水流条件的影响，选择了挖土、填土部位。通过挖泥疏浚、改变水下河槽的形式，使挟沙力达到极值，并由此建立了断面形状、尺寸所满足的驻值关系。采用迭代法求解各隐函数关系式．依次递推求得在设计流量下文山以下河道４４个断面的几何尺寸及水流要素。计算结果表明，河道挖泥疏浚后，挟沙力有明显的提高，说明挖泥疏浚工程在理论上确是一种减淤措施。

The design flow for dredging activities is determined on the basis of the scouring and silting characteristics of the channel downstream of Aishan. Observed data are used to work out the channel coarseness-velocity relation which is then used to determine the coarseness of the river bed. The section configuration impects on the flow pattern are analyzed in terms of the sediment transporting capacity. and locations for excoavation and backfill are selected. Dredging activities are to be carried out to alter configuration of the underwater channel and to maximize the silt-carrying capacity. Also. a statinnary relation is established which is satisfied by section confingurations and dinensions. Iteration is used to resolve the implicit functions and to figure out. on the analogy of this. the geometic dimensions and now elements. at the design flow. of 44 sections downstream of Aishan section.Calculations suggest that the silt-carrying capacity will be significantly improved when the dredging activities are completed. This means dredging is theoretically a sediment management measure in deed.