Evaluation of Rock Slope Stability Using 3-Dimensional Data Analysis

Abstract

The performance and maintenance of an infrastructure asset depend on the stability of adjacent structures. In this study, rail line passing through rock cut is selected to analyze the stability of the rock slopes. Generally, two-dimensional slope analysis is used to evaluate the stability of slopes owing to its simplistic and widely used approach. Three-dimensional understanding of the slope behavior is necessary to estimate the factor of safety of slopes with complex geometry. Method of columns which is an extension of method of slices, considered for most two-dimensional analyses, was used in this study to conduct three-dimensional stability analysis which requires comprehensive slope geometry data. Limitations of present traditional methods arising out of their inability to access hard-to-reach areas on the steep rock slopes have created a need for adopting new technologies. The advancement in lightweight compact sensors complimenting the robust unmanned aerial platforms have found their applications in remotely conducting qualitative and quantitative assessments of infrastructure assets. The research presented in this study discusses an approach that involves the use of aerial platform coupled with close range photogrammetry techniques to collect comprehensive rock slope data. Three-dimensional stability analysis using commercially available software was conducted by using generalized Hoek-Brown (HK) failure criterion to represent the true failure envelope of rock mass. The global minimum factor of safety of the surfaces on the rock slope was identified using Morgenstern-Price stability analysis method. This approach has resulted in significant savings in data collection time and cost, but also provided comprehensive idea about the stability of rock slopes for a given set of material properties.