Picture Butte Coal Project: A Technical Assessment of Picture Butte, 1983. (Final Report)

摘要

The observations and data obtained from the TMP at Kipp Mine, together with correlation of geotechnical data from that area and the limited geotechnical data from the Picture Butte area indicate the following: (1) Inseam physical characteristics and behavior of the coal and proximate roof and floor strata at Kipp indicate that with proper selection and application of today's coal mining technology, a longwall system of mining is possible at Picture Butte. (2) Main entries required for the long term should be driven as small as practicable and supported by arches complemented by roof bolts where required. The preferred direction of main entry driveage is south to north or north to south - the ''weak roof'' direction. (3) Service roadways for longwall retreat required for a short-term should be driven as narrow as possible, and rectangular in shape, in an east to west or west to east direction - the ''good roof'' direction. Roof bolts adjacent to the ribs of the retreat pillar of coal to be mined should be angled over the rib to help prevent roof fractures parallelling the rib line at or near the face, thereby reducing rock dilution of the coal. (4) Service roadways for longwall advance must be of the arch type, supported by rigid or yielding arches, these would also be driven in the ''good roof'' direction. Roadside packs of hardwood, anhydrite or aqua-packs can provide adequate roadway stability. (ERA citation 10:029691)