CDC STACKS serves as an archival repository of CDC-published products including scientific findings, journal articles, guidelines, recommendations, or other public health information authored or co-authored by CDC or funded partners.
As a repository, CDC STACKS retains documents in their original published format to ensure public access to scientific information.
i
Performance of a novel bump control pillar extracting technique during room-and-pillar retreat coal mining
-
1989
-
Series: Mining Publications
Details:
-
Personal Author:
-
Corporate Authors:
-
Description:"Retreat pillar mining concentrates stresses on workings directly outby gob areas, which can result in coal mine bumps. The development of bump-control design criteria by the U.S. Bureau of Mines was furthered by data from a novel bump control mining method at the Olga Mine, McDowell County, West Virginia. The pillar splitting, retreat mining system induced large pillar pressure increases and roof-to-floor convergence. Roof-to-floor convergence monitoring proved to be a valuable tool in evaluating the pillar splitting mining method and localized destressing techniques. Maximum strain energy storage in chain pillars appears to have occurred just prior to the first of four split cuts. At that point a 15-ft-wide, highly fractured perimeter confined the core of the 55- by 70-ft pillars, permitting the pillar core to support tremendous pressures. Splitting the chain pillars into two 17.5- By 70-ft wings removed the confinement load, resulting in pillar yield. Thus, the pillar splitting mining method successfully redistributed the weight of the roof away from the pillar line. Shot fire and auger drilling destressing techniques augmented the pillar splitting mining method by redistributing the weight of the roof." - NIOSHTIC-2
NIOSHTIC no. 10007018
-
Subjects:
-
Series:
-
Subseries:
-
Document Type:
-
Genre:
-
Place as Subject:
-
CIO:
-
Pages in Document:ii, 40 numbered pages
-
NIOSHTIC Number:10007018
-
Resource Number:RI 9240
-
Collection(s):
-
Main Document Checksum:
-
Download URL:
-
File Type: