Effects of hydraulic conductivity/strength anisotropy on the stability of stratified, poorly cemented rock slopes

This paper presents a numerical procedure to explore how hydraulic conductivity anisotropy and strength anisotropy affect the stability of stratified, poorly cemented rock slopes. The results provide information about the anisotropic characteristics of the medium, including the orientation of bedding planes, the anisotropic ratios of the hydraulic conductivity and the geological significance of the hydraulic conductivity anisotropy on the pore water pressure (PWP) estimation of finite slopes. Neglecting the hydraulic conductivity anisotropy of a slope with horizontal layers leads to a 40% overestimation of the safety factor. For a dip slope with inclined layers with θ = 30°, including the strength anisotropy caused a 25% reduction of the safety factor compared to the cases which isotropic strength is assumed. This paper highlights the importance of the hydraulic-conductivity anisotropy and the strength anisotropy on the stability of stratified, poorly cemented rock slopes.

► Stability analysis of slopes composed of medium with hydraulic conductivity/strength anisotropy.
► Safety factor of slope with flat layers dominated by hydraulic conductivity anisotropy.
► Neglecting the hydraulic conductivity anisotropy induced 40% overestimation of the safety factor.
► For a dip slope, including the strength anisotropy caused a 25% reduction of the safety factor.
► Geological structure strongly affects the stability of a soft rock slope.