Upper Bound Analysis of Cracked Slopes Subject to Hydraulic Effect

Ground water level fluctuations have greatly influence on stability of slopes with cracks. Pore-water pressure as the external force was involved in the calculation of energy consumption based on the upper bound limit analysis and strength reduction technique. The effect of pore-water pressure on stability of slopes with cracks was analysed. However, the change rules of critical depth or position of cracks under the effect of ground water level and slope angle was the focus of this paper. Results show that the critical position and depth of cracks significantly depend on the ground water level and slope angle. The increase in ground water level makes the critical crack close to slope crest in the case that ground water level is low. It is also observed that the influence of ground water level on critical depth of cracks presents different regularity for the case of crack position known and both crack position and depth unknown. Research results provide a new method for obtaining critical crack located on the upper surface of slopes under the complex condition.