A Method to Determine the Chain Pillar Width considering Coal Burst and Goaf Ignition Dual-Hazard Management

Abstract High rock stress and ground temperature pose great threats to the routine production of longwall top coal caving (LTCC) panels. In this risky condition, width chain pillar is considered a factor adjustable for controlling burst goaf ignition hazards. However, contradiction, as suggested by experience, that narrowing helps prevention but negatively leads higher self-ignition potentials, while widening restrains increases likelihood burst. This paper conducted case study on panel from Tangkou Mine, China. The first analysed stress, elastic strain energy, variation with varying widths, which risk index δr Qs were defined correlated D. Further, determination method considering dual-hazard management was developed means operating point principle. By method, reasonable range plotting both correlation curves δr=fD Qs=gD chart, followed optimal according intersection further verification via field trial.