Experimental study of coupling between solid and gas during drainage by advance pressure relief in mining-coal seam
Abstract：The relationship between lead abutment pressure and gas drainage quantity for differ- ent mining speeds was analysed. Solid-gas coupling during pressure unloading was experimen- tally examined for different unloading speeds and different unloading initial axial pressures. There are three stages observed in coal: A strain rebound stage~ an increasing strain stage~ and, a strain softening stage. Strain rebound is more obvious for lower initial pressures and slower unloading speeds of confining pressure. The increasing strain and strain softening stages are entered quickly with high initial pressures and rapid unloading rate of confining pressure. Axial loading for a fixed confining pressure caused a decrease in coal permeability and a de- crease in gas flow. Simultaneous decrease in confining and axial load pressures caused the per- meability to increase slowly at first but more rapidly later. At some point the permeability fluc- tuates abruptly as the confining pressure and axial load are removed. This fluctuation moves to lower unloading volume of axial pressure for higher initial axial pressure and more rapid unloa- ding of confining pressure.
Keywords：gas drainagecoupling laws of solid-gasdeformation of coalpermeability
Publication Date：2012-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：6( 900-905 )