The Role Of Engineering And Geology In Analyzing Ground Control Conditions

Newman, David A.
Organization: International Conference on Ground Control in Mining
Pages: 8
Publication Date: Jan 1, 1999
Severe roof control problems have plagued a West Virginia underground mine since its initial development in the late 1970's. Adverse roof conditions in the Eastern portion of the reserve result from a combination of mining: - perpendicular to the major principal horizontal stress direction, - near lineament intersections, - in areas where the ratio of horizontal stress to vertical stress exceeds 2.00 to 4.00, and - where laminated strata are present in the immediate roof. The focus of this study is to identify the engineering (mine orientation, roof safety factor) and geological parameters (lineament and horizontal stress orientation, horizontal to vertical stress ratio, and immediate roof lithology) causing poor roof conditions and to quantify their influence on projected mining conditions in the Western portion of the reserve Rose diagrams were used to illustrate the correlation between the orientation of eight hundred thirty-six (836) roof falls with that of forty-four (44) lineaments and the principal horizontal stress Similarly a composite map was used to demonstrate the relationship between roof falls and the ratio of horizontal stress to vertical stress The immediate roof strata across the property were categorized as either laminated or non-laminated based upon a thorough examination of one hundred sixty-two core logs. The presence or absence of fireclay, a rider coal, and carbonaceous shale was also noted because of the historic correlation with poor roof conditions. Rock strength and physical property tests were conducted on selected immediate roof strata recovered from coreholes drilled along the mains projected to the Western portion of the reserve Potential roof control problems in the Western reserve were quantified based upon the correlations developed by analyzing engineering and geological data The main conclusion is that laminated roof strata, the rider seam, and its associated fireclay will have the greatest influence on mining conditions. Roof problems attributable to horizontal stresses will not be as severe in the West due to an increase in overburden depth and corresponding decrease in the stress ratio. Recommendations are provided for mining orientation, the layout of mains and submains, panel location, and roof support based on intended service life.
Full Article Download:
(2576 kb)


Additional chapters/articles from the SME-ICGCM book Proceedings - 18th International Conference on Ground Control in Mining

Pillar Collapse at Welgedacht Colliery, South Africa: A Case
Causes of Massive Directional Roof Falls in Room and Pillar
Catastrophic Collapse Of Highwall Web Pillars And Preventati
Mine Panel Collapse - Two Case Studies
Roof Geology Mapping In Underground Coal Mines
Electromagnetic Seam Wave Mapping Of Roof Rock Conditions Ac
Geological Conditions At Continuous Miner Sections; Examples
The Role Of Engineering And Geology In Analyzing Ground Cont
The Development And Use Of Risk Assessment Techniques To Ass
Time-Dependent Analysis Of Underground Opening Stability
Tekflex As A Sprayon Screen Replacement In An Underground Ha
Tunnel Deformation Monitoring "Action Levels" In Coal Mines
Skin Failure Of Roof And Rib In Underground Coal Mines
Application Of Polyurethane Injection For Rehabilitation Of
Design Considerations For Bump-Prone Longwall Mines
Design Methodology For Standing Secondary Roof Support In Lo
Modern Shield Technology: Better Than Ever But Still Not Per
Shield Monitoring To Forecast Severe Face Weightings At The
Monitoring Of Longwall Seal Behaviour For Permeability And S
Ground Control In South African Coal Mines - A U.S. Perspect
Rock Mechanics Issues In The Trona Patch
Highwall Augering In Ultra-Thick Western Coal Reserves: Uniq
Seismic Events Due To Underground Mining Activities
Control Technology For Roof Drill Operators
Resin Annulus Size Effects On Rebar Bolt Pull Strength And R
Roof Bolt Response To Shear Stress: Laboratory Analysis
Laboratory Study Of Shear Loading And Bolt Load Transfer Mec
Analysis Of Cable Bolt Performance Using Numerical Modeling
Roof Bolting Application In Longwall Mining In Indonesia And
Ground Control Design For Multiple Seam Mining Using Finite
Pillar Design Issues For Underground Stone Mines
Calibration Of The Analysis Of Longwall Pillar Stability (AL
Mine Convergence When Using Mobile Roof Supports In Pillar R
The Advance And Relieve Mining Method: A Horizontal Stress C
Localized Horizontal Stress And Its Effect On Ground Control
Prediction And Control Of Surface Subsidence Over Abandoned
Effects Of Mining On Underground Infrastructures In The Germ
Ground Deformation In The Case Of Underground Mining Of Thic
Prevention Of Time-Dependent Subsidence By Elimination Of Gr