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Longwall Gate Road Stability in a Steeply Pitching Thick Coal Seam with a Weak Roof.

PB96135488

Publication Date	1995
Personal Author	Barron, L. R.; DeMarco, M. J.
Page Count	40
Abstract	The U.S. Bureau of Mines conducted a ground pressure analysis of a wide abutment-type chain pillar in a two-entry gate road of a Western U.S. coal mine with an extremely weak immediate roof. This report discusses gate road layout and performance and secondary support effectiveness. The results of the pillar pressure study are compared to pillar loading predicted by a widely used pillar design method and to similar studies in other mines. A stability evaluation of the most recent longwall headgate, using the USBM Analysis of Longwall Pillar Stability (ALPS) indicates marginal stability in first-panel mining and instability in second-panel mining. ALPS and the USBM Coal Mine Roof Rating (CMRR) system are used to evaluate tailgate-mining stability of the previous gate roads and to determine pillar and entry width and top coal thickness criteria for tailgate stability in future panels.
Keywords	Longwall mining Roofs Stability analysis Mine roadways Coal mines Coal seams Rock mechanics Mechanical properties Strata control Overburden Structural design Structural analysis Underground mining Mining engineering
Source Agency	Bureau of Mines
NTIS Subject Category	48A - Mineral Industries 50D - Soil & Rock Mechanics
Corporate Authors	Bureau of Mines, Denver, CO. Denver Research Center.
Document Type	Technical Report
Title Note	Rept. of investigations/1995.
NTIS Issue Number	199606

Longwall Gate Road Stability in a Steeply Pitching Thick Coal Seam with a Weak Roof.

Longwall Gate Road Stability in a Steeply Pitching Thick Coal Seam with a Weak Roof.
PB96135488

Publication Date	1995
Personal Author	Barron, L. R.; DeMarco, M. J.
Page Count	40
Abstract	The U.S. Bureau of Mines conducted a ground pressure analysis of a wide abutment-type chain pillar in a two-entry gate road of a Western U.S. coal mine with an extremely weak immediate roof. This report discusses gate road layout and performance and secondary support effectiveness. The results of the pillar pressure study are compared to pillar loading predicted by a widely used pillar design method and to similar studies in other mines. A stability evaluation of the most recent longwall headgate, using the USBM Analysis of Longwall Pillar Stability (ALPS) indicates marginal stability in first-panel mining and instability in second-panel mining. ALPS and the USBM Coal Mine Roof Rating (CMRR) system are used to evaluate tailgate-mining stability of the previous gate roads and to determine pillar and entry width and top coal thickness criteria for tailgate stability in future panels.
Keywords	Longwall mining Roofs Stability analysis Mine roadways Coal mines Coal seams Rock mechanics Mechanical properties Strata control Overburden Structural design Structural analysis Underground mining Mining engineering
Source Agency	Bureau of Mines
NTIS Subject Category	48A - Mineral Industries 50D - Soil & Rock Mechanics
Corporate Authors	Bureau of Mines, Denver, CO. Denver Research Center.
Document Type	Technical Report
Title Note	Rept. of investigations/1995.
NTIS Issue Number	199606