一种边坡临界滑动面确定方法研究

Searching critical slide surface of slope based on velocity field analysis

基于临界状态速度场的分析,提出了一种新的边坡临界状态滑动面确定方法.当坡体发生滑动时,滑动体内部各点的速率要显著大于稳定体内部各点的速率,因此,朝某个方向直线上的速率突变点即为滑动面与该直线的交点.首先通过强度折减法使边坡达到临界状态,得到边坡单元各个节点的临界状态速率场数据,然后沿竖直方向设置一系列等间距的水平线,并且在每条竖直线上布置离散点,采用插值形函数原理得到每个离散点的速率,找出每条水平线上的速率突变点,则可得到一系列表征滑动面位置的分布点,利用最小二乘法对这些分布点作平滑处理即可得到临界滑动面.最后,以一个均质边坡和一个非均质边坡为研究对象,将该方法与传统Bishop法做对比,验证了该方法的可靠性.

The velocity of the points in the sliding area is much larger than the velocity of the points stable area when the slope slide happens.Thus,the velocity mutation point located a certain line could be considered as the intersection point of this line and slide surface.Based on such understanding,firstly,the slope is led to critical state through strength reduction method to acquire the velocity of all the nodes in the slope model;and then a series of horizontal lines are evenly set up along the vertical direction and some discrete points are arranged along horizontal lines,the velocities of the above discrete points are all calculated out by shape function interpolation principle and the velocity mutation point located at each horizontal line could be founded out and smoothed by the least squares method to represent the location of the critical slide surface.Finally,a homogeneous slope and a heterogeneous slope are used for research objects,and the reliability of the proposed method is verified through the comparison of the results from the Bishop method and the proposed method.