煤矿安全2026，Vol.57Issue(7)：1-13,13.DOI:10.13347/j.cnki.mkaq.20251344
循环载荷作用下无烟煤孔裂隙及渗透率变化规律
Variation characteristics of pore-fracture and permeability of anthracite under cyclic loading
摘要
Abstract
To investigate the effects of cyclic loading on pore-fracture structure and seepage characteristics of coal,cyclic loading tests were carried out using a coal-rock multiphase and multi-field triaxial dynamic seepage experimental system.The evolution laws of pore-fracture structure and seepage characteristics of coal under different confining pressures and cyclic loading amplitudes were analyzed,and the relationship between permeability and effective stress was quantitatively discussed based on sensitivity coeffi-cients.The results show that:under a cyclic loading amplitude of 40%of the peak strength(σs),the pore-fracture space of coal samples is compressed,the proportion of meso-macropores in the three coal samples decreases by 12.63%,28.49%,and 42.91%,re-spectively,while the P-wave velocity increases;the compression degree is positively correlated with confining pressure.Permeabil-ity changes inversely with axial stress and decreases continuously with increasing cycle number,but the decreasing gradient gradu-ally diminishes;with the increase of cyclic loading amplitude(60%σs,70%σs),new pores and fractures are generated in coal samples,and the proportion of meso-macropores gradually recovers and rises,with coal sample Y3 showing the highest increase(26.53%),and the P-wave velocity decreases in all samples;the higher the cyclic loading amplitude,the more severe the coal damage,and the larger the P-wave velocity attenuation coefficient and ratio;however,high confining pressure has a certain inhibitory effect on dam-age,and the degree of P-wave velocity attenuation decreases with increasing confining pressure;in the 60%σs and 70%σs stages,per-meability first decreases and then increases during loading,and first increases,then decreases,and then increases during unloading,showing an overall irreversible downward trend;the permeability stress sensitivity coefficient generally decreases during the loading stage,while it changes relatively gently during the unloading stage,and gradually decreases and tends to stabilize with increasing cycle number;the first cycle has the most significant effect,the sensitivity coefficient during loading is generally higher than that during unloading,with the increase of peak load,the difference in sensitivity coefficients between the two stages becomes smaller.关键词
循环载荷/核磁共振/纵波波速/渗透率/敏感性系数Key words
cyclic loading/nuclear magnetic resonance/longitudinal wave velocity/permeability/sensitivity coefficient分类
矿业与冶金引用本文复制引用
郑春山,于赛宇,薛生,江丙友,韩飞林,李德星,任波,赵洋..循环载荷作用下无烟煤孔裂隙及渗透率变化规律[J].煤矿安全,2026,57(7):1-13,13.基金项目
国家自然科学基金面上资助项目(52274171) （52274171）
安徽省高校优青科研资助项目(2023AH030042) （2023AH030042）
