割压联合作用下钻孔塑性区范围分布研究  

Study on the distribution of plastic zone of borehole under the combined action of slitting and fracturing

作　　者：周应江 刘怀付 汪有清 张永将 徐遵玉[2,3] ZHOU Yingjiang;LIU Huaifu;WANG Youqing;ZHANG Yongjiang;XU Zunyu(China Coal Xinji Energy Co.,Ltd.,Huainan 232001,China;CCTEG Chongqing Research Institute,Chongqing 400037,China;State Key Laboratory of the Gas Disaster Detecting,Preventing and Emergency Controlling,Chongqing 400037,China)

机构地区：[1]中煤新集能源股份有限公司,安徽淮南232001 [2]中煤科工集团重庆研究院有限公司,重庆400037 [3]瓦斯灾害监控与应急技术国家重点实验室,重庆400037

出　　处：《矿业安全与环保》2021年第2期71-75,共5页Mining Safety & Environmental Protection

基　　金：国家重点研发计划项目(2017YFC0804209);国家重点研发计划项目(2017YFC0804206)。

摘　　要：为准确获得超高压水力割缝与水力压裂联合作用下的钻孔塑性区分布规律,基于统一强度理论,考虑煤体塑性软化和中间主应力,建立了钻孔在割压联合作用下的力学模型,推导出钻孔塑性区范围表达式,并通过算例分析了相关参数对钻孔塑性区的影响规律。研究结果表明:采用割压联合技术后,钻孔塑性区半径随着中间主应力系数的增大几乎保持不变,随着软化系数的增大而逐渐减小,随着压裂压力的增大逐渐增大;对比钻孔正常施工和超高压水力割缝情况下,钻孔塑性区半径显著增大。研究成果可为矿井更好地解决低透气性煤层瓦斯抽采治理技术难题提供一定的理论依据。In order to accurately obtain the distribution law of plastic zone of borehole under the combined action of ultra-high pressure hydraulic slit and hydraulic fracturing,based on the unified strength theory,considering the plastic softening of coal mass and the intermediate main stress,the mechanical model of borehole under the combined action of slitting and fracturing was established,the expression of plastic zone of borehole was deduced,and through the example analysis,the influence laws of relevant parameters on the plastic zone of borehole were concluded.The results show that:after using the combined action of slitting and fracturing technology,the radius of plastic zone of borehole almost remains unchanged with the increase of the intermediate principal stress coefficient,decreases with the increase of the softening coefficient,and increases with the increase of fracturing pressure;compared with the normal drilling construction and the ultra-high pressure hydraulic cutting,the radius of the plastic zone of borehole increases significantly.The research results can provide a theoretical basis for better solving the technical problem of gas drainage and control in low permeability coal seam.The research results can provide a theoretical basis for the mine to better solve the technical problems of gas drainage and control in low permeability coal seam.

关 键 词：割压联合 塑性区范围 统一强度理论 软化系数 中间主应力 压裂应力 

分 类 号：TD712+.6[矿业工程—矿井通风与安全]