瓦斯测压孔壁围岩坍塌机理及孔壁注浆加固技术  

Surrounding Rock Collapse Mechanism and Grouting Reinforcement Technology of Gas Pressure Measuring Borehole

作　　者：王法凯[1] 蒋承林[1] 吴爱军[1] 杨洋[1] 公衍伟[1] 黄鑫业[1] 

机构地区：[1]中国矿业大学煤矿瓦斯治理国家工程研究中心,江苏徐州221008

出　　处：《煤炭科学技术》2010年第9期10-13,18,共5页Coal Science and Technology

基　　金：国家重点基础研究专项经费资助项目(2006CB202204-3)

摘　　要：为了解决由瓦斯测压孔围岩松软易坍塌而导致的测压钻孔成孔困难、延误瓦斯测压时间等技术难题,用松软围岩阶梯注浆加固技术实现分阶段加固测压钻孔围岩。利用孔壁围岩坍塌机理,分析了围岩松软颗粒失稳易坍塌的力学原因;采用浆液扩散球状渗透机理,研究了浆液渗透扩散特性与围岩改造的关系。平煤股份八矿斜井石门测压应用试验结果表明:在12MPa注浆压力的作用下,松软围岩区域浆液单次渗透扩散达3.7m,3次带压注浆就解决了孔壁坍塌、抱夹钻事故对测压钻孔施工干扰的问题,最终顺利测得了煤层瓦斯压力为1.67MPa。基于孔壁坍塌机理的阶梯注浆技术实现了逐段充填松软围岩孔壁裂隙、增强围岩抗拉强度、降低切向应力集中,逐段加强围岩孔壁稳定性能,从而改善了围岩的松软特性。In order to solve the pressure measurement borehole drilling difficulty,the gas pressure measurement time delay and other technical problems occurred by the soft surround rock collapse of the gas pressure measuring boreholes,the stage grouting reinforcement technology of the soft surrounding rock could be applied to the stage grouting reinforcement of the surrounding rock for the gas pressure measuring boreholes.With the surrounding rock collapse mechanism of the borehole wall,the mechanism cause of the soft particle stability lost and easy collapse was analyzed for the surrounding rock.The diffusion ball type permeation mechanism of the grout was applied to study the relationship between the grout permeation diffusion mechanism and the surrounding rock reconstruction.The applied test results of the pressure measurements at the cross-cut of the mine inclined shaft in No.8 Mine of Pingdingshan Coal Mining Group showed that under the role of the 12 MPa grouting pressure,each permeation diffusion of grouting in the soft surrounding rock area would be 3.7 m.Three pressurized grouting operations had solved the borehole wall collapse and the drilling bit jamming accidents affected to the drilling of the pressure measuring borehole.The coal bed methane pressure of 1.67 MPa was finally and successfully measured.Based on the stage grouting technology with the borehole wall collapse mechanism,the cracking in the soft rock surrounding borehole wall could be sectionally filled,the tensile strength of the surrounding rock borehole could be steadily reinforced.Thus the soft features of the surrounding rocks could be improved.

关 键 词：孔壁围岩坍塌机理 浆液球状渗透机理 孔壁围岩松软 测压钻孔 

分 类 号：TD265.4[矿业工程—矿井建设] TD712