Methodology for Resloping of Rock Slope Using 3D Models from UAV-CRP Technology

Assessing the stability of rock slopes is essential to ensuring the typical performance of adjacent transportation infrastructures but simulating the existing field topography and boundary conditions for stability analysis is challenging. This paper describes a case study in which highly weathered rock slopes adjacent to a railroad track in Texas were analyzed using close-range photogrammetry data obtained from an unmanned aerial vehicle with close-range photogrammetry (UAV-CRP). A highly weathered rock mass with low intact strength was considered as a single continuum that undergoes circular failure and was analyzed using Spencer's two-dimensional (2D) and three-dimensional (3D) limit equilibrium method (LEM) analyses. A 3D critical slip surface was obtained to identify the critical sections on which to conduct the individual 2D stability analysis and obtain a safe resloping angle. These angles were further used to reslope the whole rock slopes and conduct a 3D analysis to arrive at a safe and economic slope angle for each side of the rock-cut. The realistic geometrical slopes developed from the aerial imagery were used to develop a framework for comprehensively analyzing the stability of a rock slope undergoing circular failure.

Automated summary

This paper discusses a case study of analyzing highly weathered rock slopes next to a railroad track in Texas using close-range photogrammetry data from an unmanned aerial vehicle. By conducting 2D and 3D limit equilibrium method analyses, safe resloping angles were obtained to determine the safe and economic slope angles for the rock-cut sides. The study showcases a comprehensive framework for assessing the stability of rock slopes undergoing circular failure based on realistic geometric slopes developed from aerial imagery.