基于强度折减法确定边坡临界滑面的小波变换法

Determination of slope critical slip surfaces using strength reduction method and wavelet transform

临界滑面的确定一直是岩土工程界研究的热点问题。利用有限元-强度折减法对二维边坡进行稳定性分析时,对于进入极限平衡状态的边坡而言,沿边坡深度方向的等效塑性应变最大值点一般也就是临界滑面上的点。然后通过预设一组相互平行且与坡面近似垂直的直线,找出各直线上等效塑性应变的最大点,可得到一系列呈波动状分布的点,这些点构成了一组一维的信号函数;再利用小波分析对数据进行平滑处理就可得到边坡的临界滑面。通过经典算例分析并与Spencer法等前人的研究成果比较,结果表明该方法是合理有效的,可以用于边坡临界滑面的确定。

The determination of positions of critical slip surfaces is a hot spot of research on geotechnical engineering. In two-dimensional slope stability analysis applied with finite element-strength reduction, the points with the maximum equivalent plastic strain along depth are mostly on the critical slip surface for a slope at limit equilibrium state. One set of wavy signal function consisting of points with the maximum equivalent strain can be constructed by deploying a series of parallel lines approximately perpendicular to the slope surface. The wavelet analysis smoothens these points on the critical slip surface. Through the classic example analysis and comparisons with Spencer＇s method and other previous research, the results show that the method in this paper is reasonable and effective, and can be used to locate the critical slip surface.