来沙条件对山区河流推移质输沙的影响  

Effects of incoming sediment on bed load transport in mountain streams

作　　者：余国安[1] 王兆印[1] 杨吉山[1] 张康[1] 

机构地区：[1]清华大学水利水电工程系,水沙科学与水利水电工程国家重点实验室,北京100084

出　　处：《清华大学学报（自然科学版）》2009年第3期341-345,共5页Journal of Tsinghua University(Science and Technology)

基　　金：国家“九七三”重点基础研究项目(2003CB415206)

摘　　要：为研究山区河流推移质输沙规律,在西南山区吊嘎河进行推移质运动野外观测和人工加沙试验。观测发现,推移质输沙与水流条件并不存在一个特定的关系,山区河流推移质输沙明显受到来沙量、来沙强度、级配等条件的影响。在同样的水流条件下,推移质输沙率在汛前和第一次洪水后可能相差数百到上千倍,推移质输沙率-水流强度关系呈顺时针"绳套型"。试验表明,粒径较小的推移质颗粒(D<20mm)运动主要决定于来沙条件,而粗颗粒泥沙的运动则主要依赖于水流条件。Field observations and experiments were conducted in the Diaoga River, a mountain stream in Southern China, to study the laws of bed load transport. The results show that there is no single relationship between the bed load transport and flow conditions, but that the bed load transport rate is greatly affected by the incoming sediment load. For the same flow conditions, the bed load discharge may be thousands of times less after the first flood of the year than before and that the bed load discharge versus stream power diagram has a clockwise looped curve. The transport rate of the bed load with diameters less than 20 mm depends mainly on the incoming rate, while the movement of coarse bed load particles is strongly related to flow intensity.

关 键 词：山区河流 推移质输沙 来沙条件 水流条件 

分 类 号：TV142.2[水利工程—水力学及河流动力学]