硬质黏土耙齿水下快速切削试验研究

Experimental study on underwater fast cutting of hard clay by draghead tooth

疏浚工程中遇到的疏浚土质变得越来越复杂,尤其在深水航道耙吸挖泥船施工中遇到的坚硬的黏性土标贯击数达到20击,与以往航道疏浚工程中黏土的坚硬状态有明显区别。为了研究硬质黏土的耙齿挖掘机理,对标贯击数18击、21击及25击的硬质黏土在不同切削速度、切削深度工况下耙齿切削阻力的变化规律进行了水下快速切削试验。试验通过在耙齿上布置切削阻力传感器的方式,得到耙齿在不同切削工况条件下的水下切削阻力,分别分析了切削速度、切削深度及黏土的标贯击数对耙齿切削阻力的影响规律,为硬质黏土耙头的设计提供了理论支撑。

The dredged soil encountered in dredging projects has become more and more complex,especially the SPT blow counts of hard clay encountered in the construction of the deep water channel with trailing suction hopper dredger reaches 20,which is obviously different from the hard state of clay in previous channel dredging projects.In order to study the excavation mechanism of draghead tooth in hard clay,underwater fast cutting experiments were conducted on hard clay with SPT blow counts of 18,21,and 25 under different cutting speeds and depths to investigate the variation of draghead tooth cutting resistance.By arranging the cutting resistance sensor on the draghead tooth,the underwater cutting resistance of the draghead tooth under different cutting conditions was obtained,and the influence of cutting speed,cutting depth and SPT blow counts of clay on the draghead tooth cutting resistance was analyzed respectively,which provides theoretical support for the design of the hard clay draghead.