摘要
泥石流和普通的山体滑坡不同,它是发生在山区的一种含有砂土和石块的暂时性水流,具有宾汉体的性质和运动阻塞双重特性,国内外众多学者在流动学实验及流动学模型的基础上,对数值模拟方法进行了大量研究,通过泥石流的灾害范围、运动速度、运动时间与实际情况进行对比,开发出适用于泥石流预报的数值模拟程序,FLO-2D就是其中之一。工程实践证明,在对泥石流组成物质的流动特性研究基础上,对泥石流移动及沉积特性进一步研究是非常重要的。本文运用FLO-2D流动模型数值模拟方法对泥石流的移动特性进行模拟,以此分析泥石流流动及堆积特性与黏性系数和屈服应力的关系。通过分析得到:随着黏性系数的增大,泥石流流速呈非线性减少;屈服应力作为影响泥石流发生及停止的因素,随着屈服应力的增大,流深也随着增大,但在泥石流移动特性中,屈服应力对泥石流流速的影响并不明显;随着黏性系数的增加,泥石流冲击力减小,而随着屈服应力的增加,泥石流的冲击力则增大。
Debris flow is different from the common landslide.It is a kind of temporary water with sand and stones occurred in a mountainous area.As researches shown,the debris flow is characterized with the nature of Bingham Body and moving jams.Many scholars had made many researches of numerical simulation method,which based on rheology experiment and model.And compared the scope,movement speed and movement time of the debris flow with the actual situation,the numerical simulation programs were developed for the forecast of debris flow.The FLO-2D is one of the software.As engineering practice proved,movement and sedimentary characteristics of debris flow is very important for further study based on the flow characteristics of research on debris flow substance composition.In order to analyze the relationship between debris flow movement-accumulation characteristics and viscosity-yield stress,we simulated the moving characteristics of debris flow by FLO-2D model.Through the analysis,we conclude that debris flow velocity is reduced with the increase of the viscosity,and the reduction isnbsp;nonlinear.With the increase of yield stress,that is one of the impact factors about debris flow occurrence and stop, flow depth increases.But among the debris flow movement characteristics,the effect between yield stress and debris flow velocity is not obvious.With the increase of the viscosity,the impact force of debris flow decreases. Meanwhile,with the increase of the yield stress,the impact force of debris flow is increased.
出处
《工程地质学报》
CSCD
北大核心
2016年第2期228-234,共7页
Journal of Engineering Geology
