Dynamic Evaluation Of Soil Slope Stability Under Rainfall Infiltration In Unsaturated

Landslide failure or debris flow which invocated by atmosphere rainfall infiltration is a common engineering disaster. As it should be admitted that the traditional evaluation method for the slope stability and the allowable safety factor theory always overestimate the design value of safety factor in a slope engineering design, for these approach only take saturated medium and hydrostatic pressure effect into consideration but influences arise out of pore water pressure by infiltration often neglected, that’s one of the reason for the geohazard happens in centralize and more rainwater region.For the above state, the aims of this study mainly include following points:1. The real-time status of matric suction was simulated under different rainfall duration and distinct evaporation time basing on the fundamental mechanics theory of unsaturated soil, meanwhile, the real-time value of shear strength which accompany by infiltration-evaporation progress was also calculated.2. The stress-strain state in a slope, which known as character of mechanical behavior response, was simulated under discrepancy rainfall duration and diverse evaporation time basing on the elasto-plastic theory.3. On the grounds of traditional limit equilibrium and reliability theory, the indicator of slope stability-factor of safety and probability of failure was calculated in a series particular situation such as various of rainfall intensity, precipitation duration and evaporation time.4. A dynamic evaluation method for the soil slope stability under rainfall infiltration was constructed and proposed by integrating three systems which are put forward above. This approach can be used in slope design and slope management.The Yongping open pit slope was taken as a practice for this technique. Basing on the engineering geology and hydrogeology condition, the stability of this system was analyzed by the method and provided a set of evaluation indicator, all of these works can be the foundation for the managerial-decision-making division of slope.