考虑水阻力的涉水滑坡运动速度计算模型研究

对于高速运动的涉水滑坡,水阻力是影响其运动速度大小的重要因素。论文设计了包括运动装置、传感装置、速度控制装置和传动装置的块体水下运动阻力的实验系统,分别进行了6块面积不同的块体分别以5种不同速度在水下运动实验,水下运动速度选取5个水平值,分别为0.5ms-1、0.8ms-1、1.0ms-1、1.5ms-1、1.8ms-1; 通过实验分析了压强水头增量与运动速度之间的相关关系,导出了水下运动块体迎水面的压强水头计算模型和迎水面阻力计算模型; 以曲线滑动型涉水滑坡为模型,分析了涉水滑坡水上部分和涉水部分受力模式; 基于滑坡动力学和运动学方程,结合条分方法,提出了曲线滑动型涉水滑坡运动速度的计算模型; 以2007年6月15日发生的清江北岸的大堰塘滑坡为例,分考虑迎水面水阻力和不考虑迎水面水阻力2种情况,分别计算了滑坡的运动速度,定量分析了水阻力对滑坡速度的影响。

MODEL TEST SPEED MODEL OF FORDING LANDSLIDE TAKING INTO ACCOUNT WATER RESISTANCE

Water resistance is one of the most important factors which affect the speed of the fording landslide when it enters water at a high speed. The experiment system is designed. It includes movement apparatus, sensor apparatus, speed control apparatus and transmission apparatus. Six blocks with different areas of water attaining surface are selected to carry out experiments. Each block moves in water at five different speeds. They are 0.5ms-1、0.8ms-1、1.0ms-1、1.5ms-1 and 1.8ms-1. The correlation between Incremental pressure head and moving speed is analyzed by experiment method. The pressure head model is established to the resistance of water attaining surface when blokes move in water. As for the curved-surface sliding model of fording landslide, the forces of sliding masses both in water and above water are calculated. The kinetics equation and kinematics equation are used to calculate landslide speeds. At last, the speed model of fording landslide is put forward by slice method when landslide moves along a curved slip surface. The paper takes the Dayantang landslide that was located on the north side of Qing River and occurred on June 15, 2007 as an example. The speeds of landslide with water resistance acting on water attaining surface are compared with those of landslide without water resistance. The influences on the landslide speed from the water resistance are quantitatively analyzed.