Underground Trials of Seismic-counter and Goafing Characteristics in Pillar Extraction
Underground trials at South African collieries of a seismic early warning instrument first developed for an Australian longwall, with analysis of how roof layers fail during pillar extraction.
by V.Z. Brink, J.N. van der Merwe & I. Canbulat | June 2003
A stand-alone device was built that detects micro-seismicity within 100 m of the roof and raises an alarm when preset thresholds are exceeded, giving early warning of goafing. Input parameters proved not to vary with geotechnical setting. Man-made noise triggering false alarms remained the main obstacle, addressed by signal conditioning and sensor placement.
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