煤矿安全2025，Vol.56Issue(10)：78-85,8.DOI:10.13347/j.cnki.mkaq.20240711
基于低场核磁共振技术的煤岩多尺度孔裂隙应力敏感性评价
Evaluation of multi-scale pore and fracture stress sensitivity in coal based on low field NMR technique
摘要
Abstract
Coal seam water injection is a widely used fully mechanized mining method for dust suppression.The pore structure and stress state change when water pressure acts on the coal during water injection,but the pore structure is the primary factor affecting the effect of coal seam water injection.In order to better reveal the evolution law of coal pore structure and stress sensitivity during coal seam water injection,low field nuclear magnetic resonance monitoring and in-situ coal seam water injection technology are used in this paper to evaluate the stress sensitivity of coal multi-scale hole fractures of drilled and undrilled coal cores respectively under the condition of dynamic load coal seam water injection.The change law of coal pore diameter and compression coefficient with coal seam water injection is quantitatively characterized,and its dynamic mechanism is described in combination with effective stress.The results show that the pore compression coefficient of different scale pores is not a constant,but changes with the change of stress,and the degree of change is related to the mode and time of stress action.Confining pressure and water pressure have opposite effects on pore compressibility at each scale,mainly due to the effect of effective stress on pore structure.关键词
煤层注水/低场核磁共振技术/孔隙结构/应力敏感性/有效应力/粉尘防治Key words
coal seam water injection/low field nuclear magnetic resonance technique/pore structure/stress sensitivity/effective stress/dust control分类
矿业与冶金引用本文复制引用
刘立仁,张小涛,王智欣..基于低场核磁共振技术的煤岩多尺度孔裂隙应力敏感性评价[J].煤矿安全,2025,56(10):78-85,8.基金项目
重庆市自然科学基金面上资助项目(cstc2021jcyj-msxmX1184) （cstc2021jcyj-msxmX1184）
