在系统分析堆积层滑坡的物质组成和位移失稳规律的基础上,根据分形理论基本原理,对该类滑坡的位移失稳过程所具有的非线性、突变性和分形降维特性进行较为深入的分析与研究。运用分形理论R/S分析法,确定滑坡位移时序分形动力学参数位移Hurst指数,并分别以三峡库区典型堆积层滑坡——新滩滑坡和黄蜡石滑坡为例,计算滑坡位移失稳过程的Hurst指数。分析和评价位移Hurst指数与边坡稳定性的关系,发现Hurst指数随着边坡由稳定向失稳的演化出现明显降维突变规律,且降维时间与滑坡整体失稳时间相吻合。这表明位移Hurst指数是堆积层边坡稳定性评价的一种有效非线性分形动力学参数,可以运用这个非线性分形参数对该类滑坡失稳演化趋势与规律进行非线性动力学评价与预测。
Based on systematic analysis of the composition landslides, a detailed research is performed on the dynamic dimension decrease in the destabilized process in terms of the and destabilized law of displacements of the debris features of the nonlinearity, catastrophe and fractal basic principle of fractals. Firstly, the displacement dynamic parameter of fractals--displacement Hurst index is determined by means of R/S analysis method. Secondly, taking the typical debris landslides--the Xintan landslide and the Huanglashi landslide as the practical examples, the correlation between the Hurst index of displacement and the stability of the Huanglashi slope is carried out; and the computation of the Hurst index of displacement during the destabilized process of the Xintan landslide is completed. It is found that the Hurst index of displacement of the Xintan landslide decreases before the destabilized time of the landslide; and the occurrence time of the Hurst index decrease agrees well with the destabilized time of the landslide. The above computational results show that the Hurst index of displacement is an effective nonlinear parameter of fractals for evaluating debris slope stability and it can be used in the nonlinear dynamic prediction for the destabilized trend of the debris landslides.