Research On The Prediction Model Of Shear Strength Of Landslide Zone Soil In The Three Gorges Reservoir Area

The study of landslide in academic and engineering circles often focuses on the systematic study of landslide soil.At present,the research on the sliding belt soil at home and abroad involves various aspects,such as the physical properties,hydrological properties,shear strength properties,microstructure and deformation mechanism of the sliding belt soil,and focuses on the strength properties.There are many factors influencing the shear strength parameters of the soil in the landslide belt,but the firms undertaking the survey are many and the level is uneven.Therefore,the correct understanding and reasonable value of the shear strength parameters of the soil in the landslide belt have been a frontier subject of indepth research in engineering and academia.This article selects landslide characteristic of qualitative variable as well as the basic physical parameters of sliding zone,the continuity of the variable as impact factors,the accumulational landslide sliding zone soil shear strength parameters c and ? value regression prediction model is established.Respectively using statistical landslide data,established the accumulational landslide sliding zone soil shear strength parameters c and ? values of virtual variables in multivariate linear regression analysis,multivariate linear regression forecast model based on principal component analysis,and with the typical landslide in the Three Gorges reservoir area as an example,the accumulational landslide sliding zone soil shear strength parameters c and ? values of regression prediction model for evaluation and testing of the model.Through the above research,the following research results are mainly obtained:1)Establish the accumulation layer landslide sample database.The existing investigation,research reports and experimental results of typical landslide disaster sites in the third and second phases of the Three Gorges reservoir area were extensively collected and sorted out,and the landslide database was established.2)Analysis on the influencing factors and distribution characteristics of the shear strength parameters of the soil in the accumulational layer landslide slip zone.Six influencing factors including slope structure type,sliding bed lithology,geological age,landslide profile form,material composition of sliding zone soil,rock content and 10 influencing factors of physical parameters of sliding zone soil were analyzed statistically.3)Influence factor variable selection and correlation analysis.The correlation coefficients of 326 continuous variables were calculated.According to the correlation coefficient between variables,there is a certain correlation among the influencing factors.For categorical variables,variance analysis,parametric test,non-parametric test(independent test,K-S test,multi-variable non-parametric test)and other methods were used to test the significance of each categorical variable at all levels.4)Establish the regression model of shear strength of soil in the slip zone.In order to eliminate the influence of different dimensions,the original data was standardized.Multivariate linear regression model with dummy variables,factor principal component analysis and multivariate linear regression model based on principal component analysis were respectively conducted for natural cohesion and natural internal friction Angle,and the standard regression model under the two methods was obtained.5)Model inspection and usage introduction.The significance and determination coefficient of the regression model were analyzed,and the regression models of various methods were summarized.The use of the model was introduced with examples.6)Model application test and evaluation.The model for predicting the shear strength of the soil in the landslide zone was applied and evaluated by 10 typical landslides in the Three Gorges reservoir area.