Mapping of Old Bords and Pillars Revisited
Desktop review of recent unmanned aerial and underwater vehicle systems and how they compare with borehole scanning, for engineers assessing the stability of old underground workings.
by Michael van Schoor (CSIR) | December 2019
Mapping abandoned, inaccessible bord and pillar workings comes down to two options: borehole deployed laser or sonar scanning, or sensors carried in by unmanned vehicles. Drone mounted laser scanning for air filled voids and sonar carried by small submersibles for flooded workings were judged the most promising, but intrinsic safety, deployment and the risk of losing equipment still favour borehole methods for occasional use.
R1500,00
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