【摘要】 为了研究突出通道渗透性对突出强度的影响规律,研制了试验装置,进行了密闭门、反滤层、金属栅栏及巷道无障碍4种揭煤试验。煤样的粒径小于4.75 mm,经15 MPa的压力压实,煤样室的内径为199 mm,煤样室总长度为1 000 mm。试验气体为N2,注气压力为0.40 MPa。采用球阀作为揭煤装置,球阀孔径为40 mm。揭煤时未对煤样施加轴向压力。试验结果表明:突出强度随突出通道渗透性的增加而增大;突出是一个由外向内发展,然后由空洞中心向四周扩展的过程;在突出的末期,随着气压梯度的降低,失稳分层厚度增大。提出将密闭门、反滤层和金属栅栏配合使用的揭煤建议。更多还原

【Abstract】 In order to study the influence of gas seepage on the stability of coal layers,some simulating tests of uncovering coal seam were made with different devices arranged in the laneway including air- tight door,metal fences,anti- fitter layers and no obstructive laneway. Coal sample is compacted by 15 MPa and its particle size distribution is less than 4. 75 mm. The inner diameter of sample cell is 199 mm and its length is 1 000 mm. CH4 is replaced by N2 during the tests,the injecting gas pressure is 0. 40 MPa. Ball valve is made as uncovering coal apparatus and its inner diameter is 40 mm. No axial pressure is loaded on coal sample during tests. Test results show that the outburst intensity decreases with the decreasing of permeability of the laneway. The outburst caves are developed from the outside to the inside and extend from the cave center to the surrounding. At the end of the outburst,the thickness of the falure sublayer increases with the decreasing of the gas pressure gradient. A suggestion is made to uncover coal seam by air- tight door,metal fences and anti- fitter layers.更多还原