Stability Evaluation of Volcanic Slopes with Crushable Particles Subjected to Freezing and Thawing

In order to elucidate failure mechanisms of volcanic slopes with crushable particles due to rainfall and freeze-thaw action, a series of rainfall tests were performed on model volcanic slopes having several water contents and slope angles. In the consideration of model test results, it was found that surface slope failures were changed depending strongly on both slope angle and the initial water content. Furthermore, it was shown that the softening of the slopes by freeze-thaw action is important for evaluating the stability of volcanic slopes; in particular, its effect is attributed to the reduction of the shearing resistance due to particle breakage, and cannot be ignored for evaluation of slope stability.