工矿自动化2026，Vol.52Issue(1)：148-153,6.DOI:10.13272/j.issn.1671-251x.2025100001
坚硬低渗煤层孔周煤体瓦斯径向渗流特性实验研究
Experimental study on radial gas seepage characteristics of coal around boreholes in hard low-permeability coal seams
摘要
Abstract
To investigate the coupling mechanism between permeability evolution of coal around boreholes and the radial stress distribution and failure characteristics in hard low-permeability coal seams,and to reveal the radial gas seepage characteristics of coal around boreholes,the radial stress distribution characteristics and fracture development degree of coal around boreholes were analyzed.Axial stress was applied using a constant-speed constant-pressure pump until coal sample failure occurred,simulating the entire process from elastic deformation to failure.By combining steady-state and transient methods,experimental studies on the radial gas seepage characteristics of coal around boreholes in hard low-permeability coal seams were conducted,and the permeability evolution characteristics during the whole deformation and failure process of coal samples were obtained.The results showed that:① coal around boreholes radially formed a crushed zone,a plastic zone,and an elastic zone in sequence.In the crushed zone,the coal structure became unstable and a large number of interconnected fractures were generated.In the plastic zone,new fractures were generated,but fracture apertures were restricted under high stress.In the elastic zone,primary fractures underwent elastic closure.② The permeability of coal around boreholes along the radial direction of the borehole decreased rapidly and then increased slowly,showing an overall distinct V-shaped variation trend.③ When the confining pressure increased from 3 MPa to 4 MPa,the permeability of coal samples decreased significantly,and the permeability under a confining pressure of 4 MPa was only 4.57％of that under 3 MPa.④ Within each stress zone along the borehole radial direction,the crushed zone exhibited the highest permeability,the plastic zone showed a stress peak and the lowest permeability,and the stress concentration phenomenon in the elastic zone gradually disappeared while permeability gradually recovered to the original permeability of the coal seam.关键词
坚硬低渗煤层/瓦斯抽采/抽采钻孔/瓦斯径向渗流/钻孔径向应力/渗透率/稳态法/瞬态法Key words
hard low-permeability coal seam/gas extraction/extraction borehole/radial gas seepage/borehole radial stress/permeability/steady-state method/transient method分类
矿业与冶金引用本文复制引用
李宇飞,杨硕,范鹏程,方智银..坚硬低渗煤层孔周煤体瓦斯径向渗流特性实验研究[J].工矿自动化,2026,52(1):148-153,6.基金项目
国家自然科学基金项目(52274191) （52274191）
河南省科技攻关项目(242102320208) （242102320208）
河南理工大学基本科研业务费专项项目(NSFRF240637). （NSFRF240637）
