NIOSHTIC-2 Publications Search

A unique approach to determining the time-dependent in situ strength of coal pillars.

Authors
Biswas-K; Mark-C; Peng-SS
Source
Proceedings of the Second International Workshop on Coal Pillar Mechanics and Design, Pittsburgh, PA: National Institute for Occupational Safety and Health, (NIOSH) 99-114, IC-9448, 1999 Jun; :5-13
NIOSHTIC No.
20033299
Abstract
In general, it cannot be assumed that the strength of coal pillars remains constant over long periods of time. Field observations indicate that a coal seam, especially when it contains a parting layer, deteriorates over time, reducing the load-bearing capacity of the pillars. This paper discusses a unique approach to determining the time-dependent strength of coal pillars in the field. Three coal pillars that were developed 5, 15, and 50 years ago were chosen for the study. Holes were drilled in coal and parting layers in each pillar, and the strength profiles were determined for each hole using a borehole penetrometer. The strength data were treated statistically to establish time-dependent strength equations for different layers. The results can be used to help estimate the loss of pillar capacity over time.
Keywords
Mining-industry; Underground-mining; Geology; Rock-mechanics; Models; Computer-models; Statistical-analysis; Risk-analysis; Room-and-pillar-mining
Publication Date
19990601
Document Type
Conference/Symposia Proceedings
Fiscal Year
1999
NIOSH Division
PRL
Source Name
Proceedings of the Second International Workshop on Coal Pillar Mechanics and Design
State
PA; WV
Page last reviewed: March 11, 2019
Content source: National Institute for Occupational Safety and Health Education and Information Division