Ground Control in Multi-level Room and Pillar Mines.
NTIS: PB/83-252965 :122 pages
This research is concerned with ground control in multiseam mining and relates mainly to the analysis of stress about multiseam room- and-pillar mines. The two variables of most concern are distance between seams and alignment of the pillars between seams. The first efforts of the investigation apply to the development phase of mining when the extraction is typically less than 50%. The second efforts are concentrated on retreat mining and barrier-pillar safety when the extraction is typically greater than 50%. The procedures in both cases are readily applicable to more than two seams. Although two-seam mines are the most frequent type of multiseam operations, because of the potential for three-seam operations in the western United States, a number of three-seam development analyses are also presented.
CP; Final Contract Report;
NTIS Accession No.
Univ. of Utah