煤矿安全2025，Vol.56Issue(6)：33-41,9.DOI:10.13347/j.cnki.mkaq.20241451
长期应力作用下煤体渗透特性与演化规律研究
Study on evolution law of coal permeability characteristics under long-term stress
摘要
Abstract
In the process of gas extraction,deep coal is affected by high ground stress for a long time.In order to explore the per-meability characteristics and evolution law of coal under long-term stress.A coal permeability model considering the interaction between creep and matrix-fracture under long-term stress is established.The internal expansion coefficient is defined to reflect the contribution of matrix expansion deformation caused by gas adsorption to the change of total volume and fracture volume,and it is introduced into the classical stress-strain constitutive equation.The experimental data based on fractional derivative transient pulse method is used to estimate the permeability and verify the accuracy of the permeability model.The results show that the permeabil-ity decreases gradually during the first and the second stages of creep caused by long-term stress,which is consistent with the physic-al process in which the initial cracks and pores are gradually compacted.In addition,compared with the existing classical models,the proposed permeability model shows better performance in describing the evolution trend of permeability.Parameter analysis shows that under constant effective volumetric strain,small internal expansion coefficient makes effective volumetric strain play a domin-ant role in permeability evolution,while large internal expansion coefficient leads to adsorption expansion strain increment playing a dominant role in permeability evolution of deep coal seam.关键词
煤层渗透率/蠕变与渗流/基质-裂隙相互作用/演化规律/瓦斯抽采Key words
coal seam permeability/creep and seepage/matrix-fracture interactions/evolutionary law/gas extraction分类
矿业与冶金引用本文复制引用
孙珍平..长期应力作用下煤体渗透特性与演化规律研究[J].煤矿安全,2025,56(6):33-41,9.基金项目
国家自然科学基金区域创新发展联合基金资助项目(U23A20601) （U23A20601）
国家重点研发计划资助项目(2023YFB3211000) （2023YFB3211000）
辽宁省自然科学基金资助项目(2022-KF-23-03,2023-MS-355) （2022-KF-23-03,2023-MS-355）
