Bulletin of the Geological Society of Malaysia, Volume 67, June 2019, pp. 105 – 111
Sharan Kumar Nagendran, Mohd Ashraf Mohamad Ismail*, Wen Yan Tung
School of Civil Engineering, Engineering Campus, Universiti Sains Malaysia, Penang, Malaysia
*Corresponding author email address: ceashraf@usm.my
Abstract: Rock slope excavation is unpreventable due to some location of infrastructure development must cut through rock hills. Therefore, an appropriate rock slope characterization should be carried out in order to prevent any possible failure. Recent advancement of drone technology has enabled the preliminary assessment on geotechnical characterization to be done in a short period of time. This paper mainly focuses on extraction of orientation and discontinuity features from drone imagery through the application of photogrammetry for rock slope stability assessment. Kinematic analysis is a method used to analyze the various modes of potential rock slope failures such as planar sliding, wedge sliding and flexural toppling that occur due to the presence of unfavorable oriented discontinuities. A drone was used to capture images from aerial and sideways, then imported to photogrammetry software to be processed. The output of the photogrammetry which is the dense cloud point would then be imported into a cloud compare software for the kinematic analysis. The orientations of discontinuities that has been extracted from the rock slope using CloudCompare software was imported into Rocscience Dips Version 7.0 software. The kinematic analysis feature of this software provides a quick check for various rock slope stability failure modes on a stereonet plot, such as planar sliding, wedge sliding and flexural toppling with just input on slope orientation, friction angle and lateral limits, before selecting the failure modes. By using discontinuity data, the kinematic analysis shows that the rock slope has 15.40% risk for planar sliding, 7.16% for wedge sliding and 1.33% for flexural toppling. Hence, the use of UAV as a tool in rock slope characterization is reliable because it can provide valuable preliminary information on rock slope stability assessment.
Keywords: UAV photogrammetry, rock slope stability, kinematic analysis, sensitivity analysis
DOI : https://doi.org/10.7186/bgsm67201913
