矿业科学学报2025，Vol.10Issue(5)：797-807,11.DOI:10.19606/j.cnki.jmst.2025105
动载作用下煤体孔隙结构演化与瓦斯渗流规律研究
The evolution of pore structure and gas seepage patterns of coal body under dynamic load
摘要
Abstract
This study explores the pore damage and gas seepage patterns of coal samples under different dynamic load through dynamic impact tests using the split Hopkinson pressure bar(SHPB)testing sys-tem.The T2 spectra and permeability of coal samples before and after different impact velocities were tested using nuclear magnetic resonance(NMR)and coal core permeability testing devices.We also analyzed the distribution of coal body pores and their damage evolution patterns.Results indicate that:As the impact velocity gradually increased,micropores and mesopores dominated the pore evolution process of coal samples,with maximum increases of 21.10％and 30.57％.Under dynamic load,the overall damage area of coal pore structure exhibited a transition from a scattered point distribution to a complex interwoven line and plane distribution.The fractal dimensions of both permeable pores and to-tal pores decreased linearly with increasing impact velocity,while the increment of porosity increased exponentially with increasing impact velocity.The permeability increment of coal samples showed an in-creasing trend with the increase of impact velocity,and the increment was most significant when the gas pressure was 0.30 MPa.The increment of coal sample permeability showed exponential decrease with the increase of gas pressure.When the impact velocity increased,the development of mesopores and macropores caused the internal gas flow state of the coal sample to shift from micropore flow to microc-rack flow,resulting in a significant increase in permeability.关键词
动载作用/核磁共振/孔隙结构/瓦斯渗流/损伤演化Key words
dynamic load/nuclear magnetic resonance/pore structure/gas seepage/damage evolution分类
矿山工程引用本文复制引用
李树刚,和递,孔祥国,林海飞,赵鹏翔,张辉,李宇航..动载作用下煤体孔隙结构演化与瓦斯渗流规律研究[J].矿业科学学报,2025,10(5):797-807,11.基金项目
国家自然科学基金(52474251,52374227) （52474251,52374227）
陕西省重点研发任务专项(2024GX-YBXM-490) （2024GX-YBXM-490）
