Research On Mechanism Of High-pressure Water Jet Cutting In Coal And Rockburst Prevention

With the deterioration of mining depth and mining conditions caused by high-energy oremining induced earthquake, leading to the frequent occurrence of rockburst.Statistics shows thatover90percent of rock burst accidents happen in coal roadways. Therefore, the study of theroadway for the earthquake relief measures and scour prevention is of great significance.According to this situation, this paper analyzes the destruction mechanism of surroundingrocks in roadways surrounding mining-induced tremor, uses research methods like theoreticalanalysis, numerical simulation and application in practice, puts forward reinforced combinationin roadway surrounding rocks,a rock burst prevention control manner,and proves theeffectiveness in earthquake and rock burst prevention in practice.The technology of high-pressure water jet cutting refers to a prevention measures directlyused in strong pressure coal mines. It uses pillar as a security barrier, when the water jet drilling,coal, water discharges through the drilling; coal around the drilling dramatic move to the channeldirection; occurring the expansion and deformation of coal and the Relative displacementbetween roof and top floor. It reduces the stress around the drilling, which play the role of coalpartial relief. The technology can also reduce the brittleness and the elastic potential energy ofcoal, increase plastic deformation.With research and analysis to technology of high-pressure water jet cutting, and simulatingbased the geological conditions of LW250203in Yanbei coal mine used FLAC2D, ANSYSsimulation software. We can know appropriate relief parameters to the face, the simulationresults shows that hole diameter d takes400mm, drill hole spacing S takes3.0m,and drillinglength L takes30m are best.Outside the30~60m range of LW250203transport trough boring head take industrial testsite on site. And monitoring the date by Yanbei coal existing scour monitoring equipentelectromagnetic radiation instruments and Poland SOS microseismic monitoring instrumentsduring the industrial test. The monitoring results show that the implement of technology ofhigh-pressure water jet cutting changes the high stress distribution of the mining face trough, sohigh stress areas expand to the deep coal wall, decreasing stress gradient of the Wall of CoalTunnel, playing a very good relief effect to the coal around roadway, and thus easing the rockburst occurred in mining face.The construction of technology of high-pressure water jet cutting has many advantages likesimple process of construction; construction safety; technical feasibility, etc, and high-pressurewater moist coal wall, reducing the dust concentration of mining face, improve the workingenvironment. Study of the project has huge economic and social benefits, which results not onlyapply to Yanbei coal, and can be used in other mining with rock burst dangerous, has a very broad application prospects.