Abstract:

In order to investigate the effect of permeability enhancement and gas drainage of waterjet rigid slotting, field test was carried out in Yangliu mine 10412 extraction tunnel. The result shows that the high pressure water slotting can form pressure relief space, which leaves the coal mass rheology and the permeability enhanced. Gas desorption and flow are boosted. Grid strengthen permeability enhancement and local effective outburst elimination can be realized through the combined arrangement of slotting boreholes and ordinary boreholes. The effect of gas drainage is strengthened if slotting inside the boreholes and the adjacent ordinary boreholes are activated if slotting between the boreholes.

Key words: outburst elimination, crossing boreholes, slotting, grid, permeability enhancement