Mine Panel Collapse - Two Case Studies

Chen, Hanjie
Organization: International Conference on Ground Control in Mining
Pages: 11
Publication Date: Jan 1, 1999
A mine panel collapse may occur when pillar sizes are too small or the surrounding rock strata (roof or floor) yields. After a small pillar fails, its loading is rapidly transferred to adjacent pillars that in turn fail. If the surrounding rock strata yield, the loading on pillars will redistribute. which may result in some pillars under high stress. This paper analyzes the causes of two cases of mine panels failures in two room and pillar mines. One case of massive pillar failure occurred in a phosphate mine and the other, mine panels failure, is in a coal mine. In the phosphate mine, both the roof and floor strata were a thick competent shale stratum. The finite element analysis shows that the major reason for the massive pillar failure is that the pillar sizes were too small in a panel. In addition, the high cliff topography has some influence on the failure. In the coal mine, the failed area was about 1,000 ft long by 760 ft wide (covering more than 3 panels) involving 390 pillars. The harrier pillars between the panels were punched on retreat into small chain pillars and the extraction ratio in this failed area was more than 80%. The roof remained intact, and pillars were crushed and punched into the floor. Based on the stress analysis, it is found that multiple panel collapse occurred because the barrier pillars were punched into small pillars and the loading on panel edges increased due to floor failure.
Full Article Download:
(2957 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