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U.S. Department of Energy
Office of Scientific and Technical Information

Analysis of retreat mining pillar stability

Conference ·
OSTI ID:124671
; ;  [1]
  1. Bureau of Mines, Pittsburgh, PA (United States). Pittsburgh Research Center

Preventing pillar line squeezes, massive pillar collapses, and coal pillar bumps is critical to the safe and efficient recovery of coal during retreat mining operations. To help prevent these problems, the US Bureau of mines has developed the Analysis of Retreat Mining Pillar Stability (ARMPS) computer program. ARMPS calculates stability factors (SF) based on estimates of the loads applied to, and the load-bearing capacities of, pillars during retreat mining operations. The program can accommodate various retreat mining scenarios including angled crosscuts, varied entry spacings, barrier pillars between the active section and old (side) gobs, and slab cuts in the barriers on retreat. It also features a pillar strength formula that considers the greater strength of rectangular pillars. The program may be used to evaluate bleeder energy designs as well as active workings. A data base of 130 pillar retreat case histories has been collected across the United States to verify the program. It was found that satisfactory conditions were very rare when the ARMPS SF was less than 0.75. Conversely, very few unsatisfactory designs were found where the ARMPS SF was greater than 1.5.

OSTI ID:
124671
Report Number(s):
CONF-950811--; ISBN 0-930284-56-9
Country of Publication:
United States
Language:
English