On the Stability of Carbon Shale Slope under Rainfall Infiltration

Carbonaceous shale is a sedimentary rock containing a large amount of dispersed carbonaceous organic material. It is easy to crack and soften when exposed to water. In the present work, the stability of such a rock and its sensitivity to the formation of infiltrations due to rainfall are analyzed numerically using the GeoStudio software. The slope stability coefficient is calculated and verified using the landslide thrust calculation method. The results show that under the action of heavy rainfall, water infiltrates into the slope layer by layer, and, accordingly, the soil volume water content is different with respect to that typical of a homogeneous soil. It is also shown that, although in an initial stage, rainfall infiltration leads to the decline of the slope stability coefficient, with the progress of rainfall, this coefficient can temporarily increase, that is, these phenomena can display a lag phase.