单向流作用下淤泥质黏土起动试验研究

Experimental Research on Onset of Muddy Clay Exposed to Unidirectional Flow

为掌握淤泥质黏土的起动规律,采用水体灰度和水流速度同步测量的方法,对不同沉积密度条件下淤泥质黏土的起动特性进行了试验研究.试验结果表明:淤泥质黏土的起动现象可用弱起动和普遍起动描述.弱起动床面冲刷率低,水体灰度值的变化约为10;普遍起动床面冲刷率明显提高,灰度曲线发生突变的附近为普遍起动,相应的灰度值变化一般超过20.普遍起动流速约为弱起动流速的1.5倍.

In order to investigate the onset law of muddy clay, the onset characteristics of muddy clay with different sedimentary densities were investigated experimentally by the synchronous measurement of water grey level and flow velocity. The experimental results show that the phenomenon of the onset of muddy clay can be divided into weak onset and general onset. To the weak onset, the rate of erosion on the muddy bed is low and the variation of water grey level is about 10. While to the general onset, the rate of erosion corresponding to a sudden change in the curve of water grey level increases evidently and the variation of water grey level is usually more than 20. The flow velocity of the general onset is 1.5 times as much as that of the weak onset.