Stability analysis and trajectory optimization of vertical and deviated boreholes using the extended-Mogi-Coulomb criterion and poly-axial test data

Many hydroelectric power stations are constructed on rock foundations. Therefore, the stability of rock slope is critical for the engineering especially in the excavation state. The analysis for consequent rock slopes is not identical with the earth slope because of their material characteristics. In this paper, it is combined the elastic-plastic finite element method and safe factor strength reduction method for the solution of problem. Considering the multi-layer material of the rock slope, Drucker- Prager criterion is adopted for determining the yield station which has the modified format of Morh-Coulomb criterion overcome the corner point problem of application proper for rock material. The conditions both of displacement mutability and cut-through of plastic zone are described in detail and research deep for failure judged. Analysis and compare of the situations which contain displacement, plastic zone between pre-excavation and post-excavation by certain numerical example, some useful results are given for stability analysis of consequent rock slope.

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Slope Stability Analysis Using Limit Equilibrium Method in Nonlinear Criterion

The Scientific World JOURNAL ◽

10.1155/2014/206062 ◽

2014 ◽

Vol 2014 ◽

pp. 1-7 ◽

Cited By ~ 5

Author(s):

Hang Lin ◽

Wenwen Zhong ◽

Wei Xiong ◽

Wenyu Tang

Keyword(s):

Stability Analysis ◽

Slope Stability ◽

Safety Factor ◽

Limit Equilibrium ◽

Friction Angle ◽

Limit Equilibrium Method ◽

Slope Stability Analysis ◽

Cohesive Strength ◽

Equilibrium Method ◽

Coulomb Criterion

In slope stability analysis, the limit equilibrium method is usually used to calculate the safety factor of slope based on Mohr-Coulomb criterion. However, Mohr-Coulomb criterion is restricted to the description of rock mass. To overcome its shortcomings, this paper combined Hoek-Brown criterion and limit equilibrium method and proposed an equation for calculating the safety factor of slope with limit equilibrium method in Hoek-Brown criterion through equivalent cohesive strength and the friction angle. Moreover, this paper investigates the impact of Hoek-Brown parameters on the safety factor of slope, which reveals that there is linear relation between equivalent cohesive strength and weakening factorD. However, there are nonlinear relations between equivalent cohesive strength and Geological Strength Index (GSI), the uniaxial compressive strength of intact rockσci, and the parameter of intact rockmi. There is nonlinear relation between the friction angle and all Hoek-Brown parameters. With the increase ofD, the safety factor of slopeFdecreases linearly; with the increase of GSI,Fincreases nonlinearly; whenσciis relatively small, the relation betweenFandσciis nonlinear, but whenσciis relatively large, the relation is linear; with the increase ofmi,Fdecreases first and then increases.

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