Weathering of the Granite Soils and Its Influence on the Stability of Slope

Abstract

The cutting slopes in granite soil regions are exposed in air and subjected to temperature change and water infiltration immediately after cutting. Then the strength of the soil mass is lowered successively up to failure point. In order to clarify the cause of the phenomena, the authors tried to examine a slope selected in a granite soil region by means of physical, chemical and mineralogical analysis. According to the results obtained from the above experiments, it is concluded that the original ground before cutting can be classified into three zones with characteristic clay minerals and the more the ground is weathered initially, the more rapidly their strength decreases excepting for the severely weathered part. These results are considered to depend largely on the fact that the soil grains weathered originally in the long period of time are relatively sensitive or unstable to chemical and mechanical actions.