Analysis Of Landslide Stability Based On Progressive Failure

China has a large mountain area,and landslide geological disasters are widely distributed.In recent years,the mountainous infrastructure construction and major people's livelihood projects are in full swing,and the urbanization construction has been steadily advancing.In these constructions,the landslide eng ineering problems cannot be avoided.Most forms of landslides are progressively damaged.There are two basic forms of traction and pedestal.They mainly represent the process of gradual development from local damage to overall destruction.Therefore,the l andslide destruction process and stability analysis base on the damage characteristics is of great significance.To solve the problem of landslide prediction and management,we must obtain the following two aspects of landslides: the first is the cause and mechanism of landslides and the destruction process,and the second is the stability analysis of landslides.This paper focuses on these two aspects of landslide research,taking the progressive failure of slope as the main line,and the landslide failure mechanism and process,landslide stability analysis for the two branches,using basic idea of “data analysis-theoretical method model-numerical calculation-model experiment” to extend the main line and extend the branch line.The authors analyzed and researched the causes of the progressive landslide,mechanical mechanism,the process of damage evolution,and the weakening law of the rock and soil mass,and put forward some new ideas and new methods.First,look for related literature and data,analyze a large number of examples of landslides,and analyze the forming mechanisms and mechanical mechanisms of the progressive landslides of the three types: retrogressive landslide,load-caused landslide and complex landslide,then analyze the temporal and spatial evolution of progressive landslides.In the case of landslides,internal and external disturbances,local stress concentration,localized damage,stress release,transfer and redistribution,destruction of the adjacent areas,continuous expansion o f the destruction area,until the penetration,the process emerged as the time and space of the mechanical response and deformation development law.Secondly,based on the relationship between the reduction coefficient of strength parameters and the determination of the comprehensive safety factor,a method of dynamic analysis of landslide stability based on progressive failure is established.According to the relationship between weakening of intensity parameters and critical state,dual strength reduction method and supporting reduction mechanism,the correlation of strength parameter reduction is established by the attenuation relation formula of strength parameters,the cohesion force changes with the reduction factor,and the internal friction angle is changed.The attenuation relation formula varies with cohesion.The strength parameters are reduced to the critical state,and the reduction coefficient of the strength parameter from the initial to the critical is determined,and the comprehensive safety factor is converted.Combined with the law of gradual damage,the reduction range of the two-strength reduction method was optimized and a dynamic local double strength reduction method was proposed.Then,based on the above two aspects,the numerical simu lation of the progressive failure process of the landslide case and the stability analysis of the dynamic local dual strength reduction method are performed,and the proposed method is verified.Finally,according to the two factors of loading and excavati on in the mechanism of the progressive landslide,a landslide model test was designed to carry out the disturbance test of the slope top loading and step foot excavation,and the mechanical response during landslide formation and development was obtained.And deformation evolution process.