黄河下游“多来多排”的输沙机理与不淤河槽设计  

Sediment Transport Mechanism of “Discharge As There Are” and Design of Un-Deposited Channel of the Lower Yellow River

作　　者：高航[1] 齐璞[1] 彭红[1] 

机构地区：[1]黄河水利科学研究院,河南郑州450003

出　　处：《人民黄河》2007年第7期14-16,共3页Yellow River

摘　　要：冲积河道的水力几何形态在不同流量时的变化,是床面形态由沙纹逐渐进入高输沙动平整床面,引起的动床阻力变化的结果。当床面形态处于不稳定状态时,河床阻力的变化使水流处于不稳定状态,形成假潮。床面处于高输沙动平整状态时,床面上存在着强烈的底沙运动,较床沙细得多的悬沙不会在河床上落淤,故形成了悬沙“多来多排”的输沙特性。因此,床面进入高输沙动平整的水流条件是控制河床不淤的临界条件。在黄河下游床沙组成的条件下,其流速1.8～2.0m/s可作为不淤设计参数,在比降一定的条件下,可设计出不同输沙流量时的河槽宽度。The variation of hydraulic geometry of an alluvial channel under the different discharge conditions is the result of resistance variation of movable bed caused by bed morphology changing from sand ripples to the dynamic leveled bed of high sediment delivery. When the bed morphology is in an unstable statement, the variation of bed resistance makes the flow unstable and forms seiche. When the bed surface is in the statement of dynamic leveled bed of high sediment delivery, the bed surface has strong bed-load movement, the suspended load, that is much finer than the bed-load will not deposit on the bed and forms the characteristic of sediment transport of “discharge as there are” of suspended load. Thus, the flow condition of dynamic leveled bed of high sediment transport is the critical condition for no deposition control. Under the conditions of the lower river composed of bed load, the 1.8-2.0 m/s velocity can be taken as a design parameter of no deposition and can design the channel width for different discharge of sediment transport under the certain conditions of gradient.

关 键 词：不淤河槽 “多来多排” 河道形态 艾山-利津河道 黄河 

分 类 号：P333[天文地球—水文科学]