通过对我国煤矿瓦斯抽采主要封孔方式的分析，认为钻孔周边裂隙发育范围研究不透彻，始封深度、封孔长度选择不合理，注浆压力偏低，聚氨酯和水泥砂浆等封孔材料不能有效封堵钻孔周边煤岩层裂隙，是造成目前我国煤矿瓦斯抽采封孔效果不理想的主要原因。论文指出，研究多重损伤条件下的抽采钻孔周边裂隙发育时效特性，确定抽采钻孔的合理始封深度和两端封堵段长度，采用合适的注浆材料，提高注浆压力，是提高“两堵一注”带压封孔方法封孔效果的技术途径。%With an analysis on the major borehole sealing methods for mine gas drainage in China,it was found that an improper study on the crack development scope of the surrounding rock along the borehole,the irrational selection of the borehole initial sealing depth and borehole sealing length,the low grouting pressure,the polyurethane and cement mortar as well as other sealing material with ineffective sealing of cracks in surrounding coal and rock along the borehole would be the main causes of irrational gas drainage borehole sealing effect in China coal mine.A technical access to improve the borehole sealing effect of the “two sealing and one grouting” pressurized borehole sealing method was provided,including the study on the crack development time effect features of the surrounding rock along the borehole under the condition of the multi damages,the determination on the rational initial sealing depth of the gas drainage borehole and the length of the sealing section between the two ends,the proper grouting material applied and the increase of grouting pressure.
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