摘要
小浪底是黄河干流上的大型水利枢纽工程，由于坝址处地质条件的限制，泄水建筑物布置在与干流垂直的风雨沟内。黄河的多泥沙特性及泄水建筑物特殊的布置形式，使得枢纽进口导墙的布置形式对泄水孔口的淤堵状况有着重要的影响。在原布置形式的基础上，提出了修改后的进口导墙布置形式并对此进行了试验研究。不同坝前水位和入库水沙条件的试验结果表明，泄水建筑物前可以形成单一逆时针方向的回流、主流顺坝流动、侧向泄流的有利流态。在此种流态下，泄水建筑物门前能够形成宽度为７０～２００ｍ、边坡为１∶５．０～１∶１．４３的小漏斗，可以保持泄水孔口不发生淤堵。
Xiaolangdi Reservoir is a large scale hydroproject located on the stem of lower Yellow River . Because of the limits of geologic structure at the dam site, water rerlief structure has to be set up on a gully that is vertical to the mainstream. Due to the characteristics of Yellow River with big sediment concentration as well as the special location of the water relief structure,layout of the guiding wall near the hydroproject inlet will yield an important impacts on the sedimentation regime. On the basis of the previous layout of the wallls,the authors proposed an amended one and conducted comparitive experimental researches.The results of the conducted experiments under various combination of water stages before the dam and incoming sediment and flow, show that under a certain layout of the walls, it is possible that main stream flows along the dam with water relieving laterally throuth the water relief structure meanwhile there exists a mono anti clockwise backflow before the structure. This was proven to be a favorable fluid state which erode the river bed in front of the structure into a funnel with a width of 70～700m, a slopes of 1:5.0 ～1:1.43. So avoiding the possibility of sediment deposition.
出处
《河南科学》
1998年第4期465-469,共5页
Henan Science
