The monitoring of the deformation of the slope and the time prediction Based on the stress-dilatancy of the soil

The measurement of the deformation of the sandy model slope under artificial rainfall or cutting were conducted to examine whether the strain increment ratio (=compression strain increment/shear strain increment ratio) can shows the stress state in the slope before the failure. In the experiment with artificial rainfall, the compression strain increment at the bottom of the slope decreased with the increase of the shear strain and then became zero just before the failure of the slope. This fact shows the strain increment ratio can be a indicator of the instability of the slope.