The outcomes show that a) each section is in the state of scouring in the first 10 years of sediment discharge series and deposition happens in the second 10 years;b) only series 2 can keep the bankfull discharge greater than 4,000 m3/s in the whole lower river channel;c) the silt-discharg.
利用黄河下游水动力学泥沙冲淤数学模型,采用3个20年设计水沙系列对河段的冲淤及平滩流量的变化进行了计算与分析,结果表明:①各水沙系列的前10年,下游各河段均处于沿程冲刷状态,而后10年各河段则出现了淤积;②只有系列2能维持整个下游河道的平滩流量在4000 m3/s以上;③各系列前10年塑造河槽阶段的水沙过程均比较合理,基本实现了平滩流量稳定增大的目的,后10年河道平滩流量则出现了不同程度的减小;④应尽量控制小浪底出库含沙量不超过200 kg/m3且细泥沙比重在75%以上。
The article analyzes the basis to build various scouring formulas and their application condition,introduces development history of the formula,and proposes the problems faced in applying these formulas and their countermeasures,in order to offer theoretical basis for further researches on river channel scour under bridge.
对各类冲刷公式建立的依据以及公式的适用条件进行了分析,介绍了公式发展历史,并提出现在应用这些公式所面临的问题以及解决方法,为桥下河槽冲刷的进一步研究提供了理论基础。
The narrow and deep channel possesses great flood discharge and silt carrying capacities,which is the target of the main channel training.
窄深河槽具有很强的泄洪能力与输沙能力,是主槽整治追求的目标。
Banks training is conducted based on narrow and deep channel in flood season that has strong potentiality of sedimen.
微弯整治基于多年游荡河道的防洪抢险经验,其能达到减小游荡范围的治理目标,但主槽没有稳定;双岸整治方案是基于窄深河槽洪水期具有很强的输沙潜力与泄洪能力。
Training the lower Yellow River into a river of narrow and deep channel can deliver hyper-sediment concentration floods, solve the issue of flood control and perfect the state strategy of ”retaining at upper stream” of the Yellow River management.
将黄河下游治理成窄深河槽,能输送高含沙洪水,进而解决防洪问题,是国家"上拦"治黄战略的完善。
Comparison of methods predicting normal depth in compound channels;
复式河槽正常水深计算方法比较
Research on momentum transfer coefficient in compound channels;
复式河槽动量输运系数研究
Computation of resistance coefficient and conveyance capacity in compound channels;
复式河槽阻力系数及过流能力计算
Based on the measured underwater topographic map of the Changjiang River estuary from 1984 to 2005,the riverbed evolution in the North Branch since 1984 is analyzed by use of the digital topographic method in aspects of the regime variation,adjustment of longitudinal and cross section and channel-fill volume variation.
根据1984~2005年实测长江口水下地形图,采用数字地形模型技术,从河势变化、河床纵横向调整、河槽容积变化等方面,分析了1984年以来长江口北支河床演变。