@article{ref1,
title="Dynamic failure in coal seams: Implications of coal composition for bump susceptibility",
journal="International journal of mining science and technology",
year="2016",
author="Lawson, Heather and Weakley, Andrew and Miller, Arthur",
volume="26",
number="1",
pages="3-8",
abstract="As a contributing factor in the dynamic failure (bumping) of coal pillars, a bump-prone coal seam has been described as one that is &quot;uncleated or poorly cleated, strong…that sustains high stresses.&quot; Despite extensive research regarding engineering controls to help reduce the risk for coal bumps, there is a paucity of research related to the properties of coal itself and how those properties might contribute to the mechanics of failures. Geographic distribution of reportable dynamic failure events reveals a highly localized clustering of incidents despite widespread mining activities. This suggests that unique, contributing geologic characteristics exist within these regions that are less prevalent elsewhere. To investigate a new approach for identifying coal characteristics that might lead to bumping, a principal component analysis (PCA) was performed on 306 coal records from the Pennsylvania State Coal Sample database to determine which characteristics were most closely linked with a positive history of reportable bumping. Selected material properties from the data records for coal samples were chosen as variables for the PCA and included petrographic, elemental, and molecular properties. <br><br>RESULTS of the PCA suggest a clear correlation between low organic sulfur content and the occurrence of dynamic failure, and a secondary correlation between volatile matter and dynamic failure phenomena. The ratio of volatile matter to sulfur in the samples shows strong correlation with bump-prone regions, with a minimum threshold value of approximately 20, while correlations determined for other petrographic and elemental variables were more ambiguous. <br><br>RESULTS suggest that the composition of the coal itself is directly linked to how likely a coal is to have experienced a reportable dynamic failure event. These compositional controls are distinct from other previously established engineering and geologic criteria and represent a missing piece to the bump prediction puzzle.<p /> <p>Language: en</p>",
language="en",
issn="2095-2686",
doi="10.1016/j.ijmst.2015.11.002",
url="http://dx.doi.org/10.1016/j.ijmst.2015.11.002"
}