Introduction

Anisotropy is an important factor in controlling the stability of rock slopes because it affects the mechanical behavior of the rock mass. Rock masses can have different mechanical properties depending on the orientation of the rock units and the orientation of discontinuities, such as fractures and joints. When the orientation of the discontinuities and the orientation of the rock mass relative to the slope are unfavorable, the rock mass may be more prone to failure, making the slope less stable. Therefore, understanding the anisotropy of a rock mass is crucial for assessing its stability and designing safe slopes.

The objective of this example is to demonstrate how GeoStudio can be used to explore the effect of joint orientation on the calculated factor of safety for an inter ramp stability. Specifically, a comparison between 2D and 3D analyses is conducted to evaluate the effect of increased joint obliquity on stability. For a 2D analysis, the only option to account for joint orientation is to calculate an apparent dip. The 3D analysis, in contrast, readily considers the orientation of the anisotropy relative to the slope angle