A new slope stability analysis for Shirasu slopes in Japan

The inter-particle force due to meniscus at a contact point of particles is derived and then the relationship between suction and apparent cohesion is numerically obtained based on some probabilistic consideration on the soil particle scale. Then a new slope stability analysis is proposed to analyze the stability of Shirasu slopes, in which Janbu method is applied to the slope failure due to heavy rainfall. In the proposed slope stability analysis the change in apparent cohesion with the change in water content due to rainfall is taken into account. The probability of slope failure can be calculated in the real time by a personal computer when the data on total amount and intensity of rainfalls are obtained in the real time.