1.Zhongyun International Engineering Co.,Ltd.,Zhengzhou ，China;2.College of Resources and Environment Engineering, Jiangxi University of Science and Technology,Ganzhou ,China

为解决采动影响下破碎煤体在瓦斯抽采过程中,钻孔密封质量差、易发生失稳破坏等难题,以平煤十三矿为工程研究背景,在钻孔失稳变形机理分析的基础上,提出采用孔口段煤体注浆固化+孔内主动支护联合防治技术以提高钻孔稳定性,并在己15-17—11030工作面进行工业性试验。工业性试验结果表明:试验孔瓦斯衰减速度较慢、抽采寿命长,其最大抽采浓度约是普通对比孔最大抽采浓度的1.3倍;在第10天,普通对比钻孔发生失稳破坏,抽采瓦斯浓度和孔口负压骤然下降,而应用该技术的试验孔始终保持高效的抽采;依靠该技术的支护作用可改善煤体物理力学参数,使破碎区煤体相互啮合并处于原位,阻止钻孔破碎区进一步扩大或恶化,保持钻孔的长期稳定和瓦斯的高效抽采。

In order to solve the problems of the borehole sealing quality is poor and borehole instability is prone to occur under the disturbance from mining activities during the gas draining process,this paper takes No.13 coal mine of Pingdingshan as the research engineering background,based on the mechanism analysis of borehole instability and deformation,this paper propose a novel technology to improve the borehole stability,which is combined curing the front-end coal of the borehole by high-strength cement mortar with the installation of screen pipes into the borehole to provide active support. The novel technology is applied on the mining face of F15-17—11030,and the industrial test results show that the testing borehole decay much more slowly and the drainage service life much longer than the conventional borehole. The maximum gas drainage concentration of testing borehole is approximately 1.3 times that of the conventional contrast borehole. Around the 10th day,the conventional contrast borehole occurre to be instability failure,the gas drainage concentration and negative pressure of suction around borehole front-end both dropped abruptly. However,the applied the technology testing borehole kept high efficiency gas drainage. Relying on the support from the screen pipe,could improve the physical and mechanical parameters of coal,making the broken the coal mesh with each other to keep the coal in suit preventing collapse and thus the stability of the borehole is improved,keeping the long-term stability of drilling and efficient gas extraction.