| Bedding landslide is the most easily deformed and unstable rock slope.Relying on the "12th Five-Year" National Science and technology support projects "catastrophe process control theory and dynamic control technology research in southwest mountainous area highway roadbed "(No.2015BAK09B00)to carry out research,through the double reduction coefficient and Abaqus subroutine function,realizes the simulation of the landslide catastrophe process with dynamic strength double reduction factor method,studied the deformation failure law of Lijiawan landslide catastrophe process,the stability evaluation.Considering the types of the structure surface,the front and rear of the rainfall,whether or not the trailing edge crack and the number of cracks,the stability calculation model of bedding rock landslide is deduced and analyzed.The main research contents are as follows:(1)Aiming at difficulties in the three-dimensional modeling of landslide caused by its complicated topography and geomorphology and problems when finite element modeling area is far beyond the survey area,inverse analysis of typical section's stability is calculated to get proper physical and mechanical parameters,the three-dimensional finite element analysis model of Li Wan landslide is completed by constructing the entity of the basic geological data of landslide and then gridding modeling.The results show that the calculated parameters are reasonable,the model hexahedral element is relatively high,the quality of the mesh is better,and the calculation is passed.(2)In order to simulate the landslide's catastrophe process,a method of dynamic strength double reduction factor method is put forward,which realizes reasonable distribution of reduction coefficients of different parts of landslide.Based on the simulation of Lijiawan landslide,the variation trend of each displacement component and the adjustment range of each stress component distribution are analyzed.The results show that the displacement mutation to break the soil in front of the most prominent,based on the cumulative rate of strain is different,can be divided into the catastrophe process stable,less stable and instable state;principal stress S11 in the middle of the road and landslide internal stress in New District obviously,principal stress S22 in the area of stress concentration significantly expands the situation of the central and central road landslide;shallow sliding zone and deep slip shear stress and different number of mutations,showed strong shear effect,with the reduction degree increased,interlaminarshear increased.(3)The stability of Lijiawan landslide is evaluated by means of instability criterion and double reduction factor.The results show that it is safer to evaluate the stability of landslide with dynamic strength double reduction factor method,after the comprehensive treatment of landslide safety reserve obtained is less than the overall strength reduction results,but the results are similar,which shows that dynamic strength double reduction factor method is used to simulate catastrophe process and evaluate stability of the landslide is reasonable.(4)Based on the basis of reasonable simplification and assumptions,different types of structural plane,before and after the rain and there is no posterior fracture and fracture number of bedding rock slope stability calculation model is deduced,it also considers the influence on the stability of the landslide force load types and flow gap have blocked factors,then the linear type the trailing edge of structure containing a single crack surface is analyzed and the influence of the slope shape,groundwater,overload of slope and earthquake load effect on landslide stability is discussed. |
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