Research On Dynamic Reliability Of A Slope For Seismic Time-history And Inverse Design For Its Anchor's Length

China is an earthquake country. Landslides triggered by an earthquake result in great losses of life and property. Because of the randomness of earthquake loading and uncertainty of slope material parameters, the reliability of the slope stability changes dynamically during an earthquake. Therefore, the concept of dynamic reliability for time-history is proposed and the inverse design method for slope works is developed based on this concept. The main contents and the research results of this thesis are listed as follows.1,The time-history dynamic reliability concept is proposed to analyze the changes in reliability of slopes during the entire process of earthquake action, in which the randomness of both geotechnical material parameters and earthquake loading is taken into account.2,The dynamic finite element analysis of the slope is performed using the orthogonal test design method according to the variability of the material parameters to analyze the peak velocity distribution and the characteristics of dynamic response.3,The random dynamic response model is established for Stochastic parameters of a slope using artificial neural network. Four methods of calculating time-history dynamic reliability are developed based on dynamic finite element and artificial neural network,which include finite element-artificial neural network-Monte Carlo method(FEM-ANN-MCS),finite element-artificial neural network-response surface method (FEM-ANN-RSM),finite element-artificial neural network-maximum entropy approximation ( FEM-ANN-MEA ),finite element-artificial neural network-least square approximation(FEM-ANN-LSA). The merits, shortcomings and applicability of the four methods are investigated through an engineering example of an actual soil slope.4,The inverse design method for anchors used in slope works is developed based on the proposed FEM-ANN-RSM method. The inverse design method is also developed based on the proposed FEM-ANN-MCS method using the logic of the enumeration method. These two methods are applied to an actual anchored slope to determine the length of anchors.Results of the investigation indicate the proposed time-history dynamic reliability can describe well changes in the reliability of slope during the entire seismic process. The proposed methods for calculating time-history dynamic reliability (FEM-ANN-MCS,FEM-ANN-RSM,FEM- ANN-MEA ) have high precision and can be used to evaluate seismic slope stability. The FEM-ANN-MCS method is more applicable in the inverse design of anchored slope works.