METHOD OF UPPER BOUND LIMIT ANALYSIS FOR PLANE SLIDING OF ROCK SLOPES

In order to calculate and compare with the traditional rigid critical equilibrium method, this paper puts forward a new method of upper bound limit analysis for plane sliding of rock slope on the basis of limit analysis theory. By taking into consideration of the equivalent condition between the internal energy dissipation produced in the slip surface and the outer work done by external force, the upper bound solution for plane sliding of rock slope stability analysis can be deduced by means of strength reduction method. The new method can analyze different influencing factors including the hydrostatic pressure in back fissure, uplift pressure along slip surface, self-weight, horizontal seismic inertia force and anchorage force. The approaching channel inside slope of the spillway tunnel in the right bank of Jinping First Stage Hydropower Station is a typical multilevel step-shaped rock slope. The rock mass structure of the slope is stratified structure, and the potential mode of failure is plane sliding. The calculation results show that the new method of upper bound limit analysis is applicable to plane sliding of rock slope stability and is consistent with the rigid critical equilibrium method. Furthermore, it is a useful checking calculation approach for traditional method.