If you have access to OneMine as part of a member benefit, log in through your member association website for a seamless user experience.
|Coal mining both with longwall and room-and-pillar method often encounters severe operational difficulties due to had roof conditions. Rooffalls at entry cross-cuts or along the rib line in longwalls as welt as dynamic and excessive loads on supports due to overhanging of strong roof layers in a goab - are well known phenomena to the mine operators. Also, a number of practical examples may be quoted of dramatic improvement of working conditions after changing of coal winning technology or supports type. It is therefore a question to be answered how far we are able to recognize roof strata properties before mining starts and adjust both coal extraction technology and supports of entries to rock stability foreseen. Furthermore, engineering principles and criteria for decision making should be established. In recent years several in situ rock strength and discontinuities detection testing techniques have been developed both indirect (geophysical) and direct thus making possible closer roof-strata examination. In this paper critical roof span criterion is discussed as a basis for selection of proper mining system in terms of desirable stability of mine opening .|
Additional chapters/articles from the SME-ICGCM book Proceedings Second Conference On Ground Control In Mining
|A New Approach To The Design Of Multi-Entry Developments For||Manifestation Of Mine Pressure And Its Relations To Overlyin||Geotechnical Investigation For A Single Entry Design For Lon||Roof Falls And Caving In Longwall Mining Operations||Support Resistance And Roof Behaviour Of A Longwall Face Wit||State Of The Art Testing Of Powered Roof Supports||Some Structural Aspects Of Designing The Shield Supports||Design Considerations For Angle Bolters||Machine Design Parameters For High Seam Truss Bolting Applic||Design Trade-Off For Angle Roof Drilling||Hydraulic Tensioning Of A Birmingham Roof Truss||Current Trends In Roof Truss Hardware||The Search For A Method To Provide Warning Of Coal And Gas O||Methods Used To Monitor Roof Geology And Entry Supports||A Method For Estimating Western Coal Strengths From Point Lo||Coping With High Lateral Stresses In An Underground Illinois||Alternatives For Controlling Cutter Roof In Coal Mines||Remote Sensing Techniques In Mine Planning - Applications An||The Use Of A Graphic Mini-Computer System As A Rock Mechanic||Greater Safety With Increased Productivity Coal Mining Opera||Critical Roof Span Approach To Selection Of Proper Coal Mine||Roof Bolt Bond Tester; A Device For Nondestructive Testing O||Remote Control Roof Bolting||Development Cooperation Between Operator And Manufacturer -||Research, Development, And Use Of Steel-Fiber-Reinforced Con||TV Borehole Inspection And Vacuum Testing Of Roof Strata||Use Of Automated Resistivity System To Locate Potential Subs||Control Of Mine Subsidence Utilizing Coal Ash As A Backfill||Surface Flooding-Considerations For Mining Facilities Site S||The Formation And Effects Of Transient Abutment Stress Durin||Some Technical Considerations When Mining Under Bodies Of Wa|