易贡高速远程滑坡近程凌空飞行数值分析

Numerical Analysis on the Flying of Yigong High-Speed and Long Runout Landslide at the Short-Range Stage

研究了大型高速远程滑坡近程凌空飞行的空气动力学效应,建立了考虑地面效应的滑体运动微分方程组,并以易贡滑坡为例,使用数值分析方法研究高速滑体凌空飞行的运动规律.结果表明,高速滑体因空气动力学效应的影响而产生不断增大的水平推力和竖向抬升力,导致滑体的水平速度不断增大,但增幅不大,而竖向速度增幅减缓.因此,与忽略空气动力学效应的情况相比,高速滑体凌空飞行时间更长,飞行距离更远,更加符合滑坡的实际情况.

Many large high-speed and long runout landslides could fly in the air at the short-range stage.The aerodynamic effect was studied for the case of high-speed sliding mass flying at the short-range stage.The motion differential equations were educed in consideration of the ground effect.Taking the Yigong landslide in China as an example,this paper applied the numerical analysis method to study the flying law of high-speed sliding mass.The calculated results illustrate that,because of the aerodynamic effect to the sliding mass,the horizontal thrust force and vertical lift force both increase.The horizontal speed increases,but its amplitude is little.At the same time,the vertical speed tends to increase more slowly.Therefore,the flying time is longer and the distance is farther than those without consideration of the aerodynamic effect.The results are more reasonable by comparison with the field observation.