Step-Like Displacement Prediction of Landslide Based on Time Series Decomposition and Multivariate Chaotic Model

Huang Faming; Yin Kunlong; Yang Beibei; Li Xi; Liu Lei; Fu Xiaolin; Liu Xiaowen

Abstract：The GPS monitoring cumulative displacement on reservoir landslides in the Three Gorges Reservoir area shows step-like characteristics and is a probable chaotic time series under the influences of the seasonal rainfall and reservoir water level fluctuation.Traditionally,the uni-variable chaotic model is commonly used to predict the landslide displacement;and all exist-ing multivariable models select the input variables empirically without theoretical exploration of the nonlinear dynamic evolution process of landslide displacement and its inducing factors.A new combined model based on double exponential smoothing (DES),multivariable chaotic model,extreme learning machine(ELM)is proposed in this study.First,the chaos characteristic of landslide displacement is identified by the combined DES and multivariable chaotic ELM.Second,the DES method is used to predict the cumulative displacement.The predictive results are the trend displacement,and the periodic displacement is ob-tained by reducing the trend displacement from the cumulative displacement.Third,the multivariate phase space reconstruction method of chaotic theory is used to explore the dynamic relationship between the periodic displacement and its inducing factors, and the ELM model is established to predict the periodic displacement.Finally,the total forecast cumulative displacement is obtained by adding the predictive trend and periodic displacement.The GPS monitoring cumulative displacement on the Baishuihe landslide is used as case study.In addition,the proposed model is compared with the combined DES and multivariable chaotic particle swarm optimized support vector machine model,the combined DES and uni-variable chaotic ELM model.The results show that the prediction accuracy of the proposed model is higher than that of other models.The proposed model ex-plores the nonlinear characteristic of landslide displacement and its dynamic relationship with inducing factors.The model also reflects the physical meaning of the nonlinear evolution of the landslide displacement.