Stability Analysis of Cut Slopes in Ohio, USA: A Quantitative Approach

Orientation of discontinuities, in relation to slope face, is the primary factor influencing stability of most rock slopes. Kinematic analysis is the frequently used method for evaluating potential modes of failure due to unfavorably oriented discontinuities. The analysis is performed using stereonets. The procedure requires identifying discontinuity cluster sets and assigning representative values for each cluster set. A major problem with stereonet-based approach is that it does not take into account the variability in orientations of varying discontinuities. This study proposes a quantitative approach that uses all discontinuity data, not just the representative values indicated by discontinuity clusters. Discontinuity orientation data from 12 cut slopes along Ohio’s highways. DipAnalyst 2.0 software was used to demonstrate the application of the proposed approach. The results from the quantitative approach were compared with those from the stereonet-based kinematic analysis. Similar to the quantitative kinematic analysis, factor of safety values (against plane and wedge failures) for all discontinuities and their possible intersection lines were also calculated using DipAnalyst 2.0 software.