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Details

Entry Stabilization Utilizing Rib Bolting Procedures.

PB91230276

Publication Date	1991
Personal Author	Dolinar, D. R.; Tadolini, S. C.
Page Count	19
Abstract	The danger to personnel, equipment, and pillar structure created by the spalling of a coal rib can be minimized by installing rib bolts. To assure that a configured support system will maintain a coal rib, the U.S. Bureau of Mines developed a rib bolt system based on a nonpreventable failure concept. A statistical equation quantitatively related the amount of rib retained to the bolt spacing and the width of the spalled material. Laboratory test results show that the equation accurately predicts the amount of material retained and confirm the validity of the support concept. The examination of rib bolting at a coal mine experiencing rib sloughage provides evidence that the effectiveness of the support can be related to the failure pattern of the spalled material. An analysis of roof and roof support reaction to rib sloughage at the mine indicated that the rib sloughage had little effect on roof stability. Although supporting ribs might not affect roof stability, laboratory test results indicate that the material retained by the support can sustain a load up to 20 pct of the intact compressive strength of the material.
Keywords	Underground supporting Stabilization Coal mines Bolting Ribs(Supports) Coal deposits Compressive strength Mining engineering Rock mechanics Bolts Columns(Supports) Design criteria Performance evaluation
Source Agency	Bureau of Mines
NTIS Subject Category	48A - Mineral Industries
Corporate Authors	Bureau of Mines, Denver, CO. Denver Research Center.
Supplemental Notes	Library of Congress catalog card no. 90-22805.
Document Type	Technical Report
Title Note	Rept. of investigations/1991.
NTIS Issue Number	199122

Entry Stabilization Utilizing Rib Bolting Procedures.

Entry Stabilization Utilizing Rib Bolting Procedures.
PB91230276

Publication Date	1991
Personal Author	Dolinar, D. R.; Tadolini, S. C.
Page Count	19
Abstract	The danger to personnel, equipment, and pillar structure created by the spalling of a coal rib can be minimized by installing rib bolts. To assure that a configured support system will maintain a coal rib, the U.S. Bureau of Mines developed a rib bolt system based on a nonpreventable failure concept. A statistical equation quantitatively related the amount of rib retained to the bolt spacing and the width of the spalled material. Laboratory test results show that the equation accurately predicts the amount of material retained and confirm the validity of the support concept. The examination of rib bolting at a coal mine experiencing rib sloughage provides evidence that the effectiveness of the support can be related to the failure pattern of the spalled material. An analysis of roof and roof support reaction to rib sloughage at the mine indicated that the rib sloughage had little effect on roof stability. Although supporting ribs might not affect roof stability, laboratory test results indicate that the material retained by the support can sustain a load up to 20 pct of the intact compressive strength of the material.
Keywords	Underground supporting Stabilization Coal mines Bolting Ribs(Supports) Coal deposits Compressive strength Mining engineering Rock mechanics Bolts Columns(Supports) Design criteria Performance evaluation
Source Agency	Bureau of Mines
NTIS Subject Category	48A - Mineral Industries
Corporate Authors	Bureau of Mines, Denver, CO. Denver Research Center.
Supplemental Notes	Library of Congress catalog card no. 90-22805.
Document Type	Technical Report
Title Note	Rept. of investigations/1991.
NTIS Issue Number	199122