Study On The Application Of Ellipse Criterion To Slope Stability And Safety Analysis

Slope stability and safety analysis is a very important technical content for landslide risk assessment,slope reinforcement design and slope treatment engineering effect evaluation.However,the Mohr-Coulomb strength criterion based on linear change relation is used in the traditional limit equilibrium stability analysis calculation.The failure strength of rock mass and soil under low confining pressure and high confining pressure may be overestimated,which affects the reliability of calculation results of stability coefficient.In order to solve this practical engineering problem,this paper introduces the recently developed elliptical strength criterion into the calculation relation of slope stability safety coefficient,and put forward the application research of ellipse criterion for slope stability and safety analysis.First,the basic characteristics of the ellipse criterion are systematically analyzed,.The spatial expression of principal stress applied to the description of mechanical behavior of rock and soil medium is derived.The comparison with the experimental triaxial results shows that the ellipse criterion can be directly applied to the analysis of geotechnical behavior.In view of the shortcomings of the elliptic criterion,an extended relation of the elliptic criterion is given on the basis of the energy balance at one point of the failure surface.Therefore,a new criterion of failure is established,that is,the energy criterion,and involved four material constants.But the physical implications are clear.Compared with the experimental results,the energy criterion not only shows good data fitting ability,but also has certain theoretical prediction abilityIn order to extend the proposed energy criterion to the calculation relation of slope stability coefficient,the correlation analysis between the strength criterion and Mohr-Coulomb strength criterion was further given.The transformation relation between them is established,which lays a foundation for the extended relation,that is energy criterion,of the ellipse criterion to be used in slope stability and safety analysis.Finally,based on the Swedish circular arc method and Bishop simplified method,the relationship between them and the slope stability safety coefficient corresponding to the energy criterion after the expansion of the ellipse criterion is given.The analysis and calculation of four typical examples show that the theoretical results of the application of the ellipse criterion are in good agreement with the theoretical results of the traditional Mohr-Coulomb criterion.However,the elliptical criterion is closer to the answer recommended by the referee,indicating the potential technical value of applying it to slope stability and safety analysis.