Experimental Study on the Micro-Porous Characteristics and Permeability of Coal Rocks of an Outburst Coal mine
Coal samples are collected from a coal-and gasoutburst mine. The micro-structural, micro-porous, and micro-fissure characteristics of the samples are observed using scanning electronic microscope. Electro-hydraulic servo tests of four standard coal samples under complete stress-strain process are conducted by using the MTS815.02 rock mechanics testing system and the numerically controlled transient permeability method. Based on the experimental results, the Darcy flow permeability, non-Darcy flow permeability, non-Darcy flow factor β, and acceleration coefficient are calculated for different strains during the course of destruction of the coal samples. These relationship curves are obtained: principal stress difference vs. axial strain, permeability vs. axial strain, non-Darcy flow factor p vs. axial strain, and acceleration coefficient vs. axial strain. The study shows that the structures of the coal samples are nonhomogeneous, consisting mainly of grain-, grid-, and sheet-shaped structures, with some scale-shaped structures and some twisted structures being seen; that because of the action of confining pressure, during the course of destruction of coal samples, the permeability under complete stress-strain process changes as the strain increases, but does not change significantly; and that the non-Darcy flow factor β and acceleration coefficient have the same change tendency and are both negative.
coal complete stress-strain permeability-strain equation permeability
ZHANG Tianjun LI Shugang ZHANG Taowei
College of Science, Xian University of Science and Technology, Xian 710054, Shaanxi, China College of Energy, Xian University of Science and Technology, Xian 710054, Shaanxi, China
国际会议
The 2010 International Symposium on Safety Science and Technology(2010 安全科学与技术国际会议)
杭州
英文
1662-1666
2010-10-26（万方平台首次上网日期，不代表论文的发表时间）