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Photogrammetry is becoming a more common method for mapping geological and structural features in underground mines. The issue of capturing geological and structural data in inaccessible areas of mines, such as those that are unsupported, remains even when utilizing photogrammetric methods; thus, geological models of mines are left with incomplete datasets. The implementation of Unmanned Aerial Vehicles (UAVs) underground has allowed for experimentation with photogrammetry conducted from a UAV platform. This paper contains the results of an investigation focused on collecting UAV-based imagery at underground locations within Barrick Gold Corporation’s Golden Sunlight Mine in Whitehall, Montana, and the use of the imagery to produce 3D models for mapping geologic features. The primary components of the study described are the underground imagery acquisition experiences and a comparison of underground photogrammetry modeling with UAV imagery using two sets of software: a) ADAM Technology’s 3DM CalibCam and 3DM Analyst and b) Bentley’s ContextCapture for 3D modeling combined with Split Engineering’s Split-FX for mapping. The lessons learned during this study may help guide future efforts using UAVs for capturing geologic data, as well as to help monitor stability in areas that are inaccessible.
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Geotechnical Characterization of Underground Mine Excavations from UAV-Captured Photogrammetric & Thermal Imagery
Geotechnical characterization of rock masses in underground mines often involves physical measurements in supported excavations. However, unsupported stopes and drifts prevent safe access for mapping by geotechnical personnel. The advent of inexpensive, open platform unmanned aerial vehicles (UAVs) allows geotechnical personnel to characterize hazardous rock masses by utilizing traditional photogrammetric and FLIR (forward looking infrared) imagery techniques. The photogrammetric imagery can be used to capture geological structural data from the rock mass for kinematic and numerical analyses, as well as for generating geological models. In particular, the FLIR imagery has the potential to assist in identifying areas of loose rock, which typically goes unnoticed until it becomes a hazard. This paper summarizes the results of a study involving UAV flights underground at the Barrick Golden Sunlight Mine, the generation of 3D models from UAV-captured imagery, and the identification of geological data from photogrammetry models. Results confirm that the combination of off-the-shelf technologies used in this study can be successfully employed as a geotechnical tool in the underground mining environment.
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- Award ID(s):
- 1742880
- PAR ID:
- 10066204
- Date Published:
- Journal Name:
- Proceedings of the 52nd US Rock Mechanics / Geomechanics Symposium
- Page Range / eLocation ID:
- Paper 18-508
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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