Papers by Keyword: Limit Equilibrium

Abstract: The analysis of the slope stability is important in soil conservation. To analyze the slope stability, optimization methods were coded and compared with the traditional experience-based methods. Furthermore, the results were visualized in the program, so that the user can easily check the results and can designate an area, in which the program seeks the center and radius of the most hazardous slide arc. Moreover, the graphic interaction function was implemented in the program. In addition, the Standard Model One, recommended by ACAD (The Association for Computer Aided Design), was calculated by the program, of which the results (safety factor Ks=0.95~0.96) were smaller than the official recommend value (Ks=1). It is because that the traditional slice method, which neglects the normal stress and shear stress between the slices, was applied for calculation of Ks.

Abstract: This paper uses finite element numerical simulation method to analyze the rock mass stress deformation characteristic and it illustrates that site stress state is mainly controlled by the gravitational field, while the rock basic deformation is solidification. On the foundation of blocks limit equilibrium calculation results, it shows that the global stability of the site is in good condition in a variety of extreme circumstance conditions. The blocks stability is slightly lower than sites whole stability, which is in the front edge of the site, controlled by secondary slip surface II.

Abstract: In order to analyze the influence of bolt supporting parameters on the stability of slope, based on the limit equilibrium method to establish model of slope and calculated the safety factor of slope. Research shows that: (1) As the bolt length increases, the safety factor of slope increases gradually, then the length of anchor bolt can be used as the design length when the safety factor can meet the standard requirement.(2) With the increase of the anchor Angle, the safety factor of slope present the trend of first increasing and then decreasing, when bolt spacing increased to a certain value, the safety factor of slope reduce significantly.(3)In this paper, the analysis method of slope bolting parameters on its effect to the stability is simple and strong operational, which can provide a reference for related engineering personnel.

Abstract: The unstable failure of slope is frequent and the prevention is high difficult in the process of engineering construction. To provide reference for the prevention and control of slope landslide disaster, this paper take an engineer slope as the study background and make the strength stability analysis and evaluation of this slope. Through simulating different conditions by using the current comparatively mature limit equilibrium theory, analyzed and evaluated the stability of the slope under the conditions of precipitation, drainage and reinforced and master stability condition of this slope in the corresponding condition. The slope stability evaluation analysis results under different conditions showed that the landslide is more easily to take place under the conditions of natural state, heavy rainfall and earthquake. Slope stability improved in the drainage condition. At the same time, this paper combined the evaluation results of the analysis, putting forward prevention measures and suggestions for slope.

Abstract: There are corresponding stability criterions for limit equilibrium method, which is simple to implement and has been used for long-term. But this method is only considered the equilibrium of system without considering deformation, compatibility conditions and material constitutive. To improve the method, which is used to analysis the stability of Lanna dam, was proposed to optimize the boundary conditions, consider the discontinuity between the media in junction and add additional stress to consider the effects of buoyancy and seepage. After completion, tests showed that this approach could overcome limit equilibrium method’s shortcoming and describe the discontinuous characteristics of media naturally, such as dislocation, opening, slip and so on. And the result is reliable.

Abstract: Floor heave is a kind of deformation form that rock and soil mass of roadway floor enter a plastic flow state under surrounding stress. Installing anti-slide piles is an effective method to control floor heave. Considering the stress conditions and the characteristic of slip line fields in geometry size when floor heave emerges, some parameters used to design anti-slide piles are proposed to control floor heave, which will provide theoretical basis for further designs of roadway support.

Abstract: The effect of anisotropy of friction angle in natural deposited soil on the stability of soil slopes was studied in this paper. Stability analysis was performed on a uniform soil slope with anisotropic friction angle. Spencer’s method was used, and the variation of friction angle was assumed to be linear to the change of direction of the slip surface. It was shown that 7-10 percent of change in safety factor might achieve within a 10m-highed anisotropic soil slope. It was also found from the analysis that that frictional anisotropy had no obvious effect on the location of critical slip surface.

Abstract: The Various methods of optimization or random search have been developed for locating the critical slip surface of a slope and the related minimum safety factor in the limit equilibrium stability analysis of slope. But all these methods are based on a two-dimensional (2D) method and no one had been adapted for a search of the three-dimensional (3D) critical slip surface. In this paper, a new Monte Carlo random simulating method has been proposed to identify the 3D critical slip surface, in which assuming the initial slip to be the lower part of an ellipsoid, the 3D critical slip surface in the 3D slope stability analysis is located by minimizing the 3D safety factor of limit equilibrium approach. Based on the column-based three-dimensional limit equilibrium slope stability analysis models, new Geographic Information Systems (GIS) grid-based 3D deterministic limit equilibrium models are developed to calculate the 3D safety factors. Several practical examples, of obtained minimum safety factor and its critical slip surface by a 2D optimization or random technique, are extended to 3D slope problems to locate the 3D critical slip surface and to compare with the 2D results. The results shows that, comparing with the 2D results, the resulting 3D critical slip surface has no apparent difference only from a cross section, but the associated 3D safety factor is definitely higher.

Abstract: Ningde nuclear power plant in Fujian province is one of the national key construction projects of nuclear power, in order to insure the smooth progress of construction project, it needs to assess the rock slope stability which lies in the southeast of the living area. On the base of the rock architectural feature, the qualitative analysis, the three-dimensional limit equilibrium and the three-dimensional finite element are adopted to analyze the stability of the slope. The result of the qualitative analysis shows that most of the slope is stable, and part of it may fail after excavation. The result of the three-dimensional limit equilibrium and the three-dimensional finite element both illustrate that the slope is stable after excavation with slope ratio 1:0.25,1:0.50 and 1:0.75, and the stability factor rises with the decreasing of the slope ratio. At last, according to the above computing result, the 1:0.50 or the minor value is suggested to be adopted as the design slope ratio to excavate the slope.

Abstract: There have some advantages like as Good working conditions, High Security, Guaranteed production capacity and Low loss for Open pit mining, therefore the degree of opencast mining increasing. In this paper numerical simulation and limit equilibrium are used for Stability of west project of side slope which are under the conditions of Normal and Saturation. Draw slope stability results under the two conditions in order to take appropriate measures to provide appropriate post- mining safety protection.