基于改进Shannon伪近邻法研究易滑地层位移变形时序

Evaluation of Displacement Time Series in Landslide Prone Stratum Based on Shannon False Neighbors Model

合理地运用科学的理论方法,研究计算滑移地层的滑移规律并进行有效的预测,一直是亟待解决的岩土工程问题。通过基于Shannon伪近邻法时序分析理论研究易滑岩层变形破坏的演变机理;通过边坡演变的动力学方程组,建立相空间重构,得出显示边坡系统动态特性延迟时间与关联维数的计算公式,并对边坡变形破坏过程进行了实例分析,得到最佳嵌入维数取值,提取和恢复边坡系统原有的规律。在古树屋滑坡位移的外推预测中,模型计算相对误差都控制在2%以内,计算结果接近于实测位移值。工程实践表明,基于该模型的时序预测方法,在边坡位移初始变形和等速变形阶段,能保证95%以上的拟合控制精度。

How to utilize the reasonable theory to research the rule of slipping prone stratum and carrie on the effective forecasting,it is always urgently demanded for the solution of geotechnical engineering.Shannon false neighbors model of time series theory are used to study the mechanism of slippery prone stratum deformation destruction.The equations of dynamics for slope evolution are founded based on the process of slope deformation.With the reconstruction in phase space,the formulas of relative dimension and delay time which represent the dynamic characteristics of slope are obtained.The Shannon false neighbors model could get the optimal embedding dimension,extract and restore the original slope system by analyzing the process of slope deformation destruction.The calculated results of Gushuwu slope based on this new model show that the relative error may be controlled to be within 2%,the preliminary result is similar to actual displacement value.Engineering practice also prove that this model could ensure forecasting precision more than 95% during the initial deformation stage and constant deformation stage,and it is a kind of model that is worth further discussing.