黄河下游洪峰流量对断面塑造作用的试验研究

根据泥沙动床模型试验结果,探讨了黄河下游不同洪水洪峰流量下断面的冲淤及形态响应、洪峰含沙量对河槽塑造过程中水流运动、泥沙冲淤、主槽形态及过流输沙能力影响等问题,研究结果表明,断面响应与洪峰流量大小、历时、来沙系数及初始断面形态有关,大漫滩与一般漫滩洪峰流量对断面塑造特性有明显的不同,弯顶断面和顺直断面具有不同的冲淤特性,研究得到大漫滩、一般漫滩及不漫滩洪峰流量下断面的响应模式,建立了典型断面形态参数对一般漫滩及不漫滩洪峰流量下水量、来沙系数参数响应的经验关系式.

Experimental study on effects of flood peak discharge on formation of cross-section in the lower Yellow River

Based on the experimental data of a physical model with movable bed, this paper analyzes the deposition/ erosion and the morphological responses of channel under different flood discharges. The influence of the suspended sediment concentration on flow and sediment transport, main channel variation and conveying capacity of flow and sediment is also studied. The research results show that the responses of channel are related to the flood peak discharge, the duration of flood, the incoming flow-sediment coefficient and the initial cross-section pattern. The impacts of large over-floodplain floods and ordinary over-floodplain floods on the channel variation are quite different. The evolution of the cross-sections in the river bend is different from that in the straight reach. The responding modes of cross-sections under different flood discharges are acquired. The empirical relationship between the morphological parameters and the flow-sediment coefficient at typical cross-sections is established for ordinary over-floodplain floods and non-over floodplain floods.