Permeability Determination of Gas-bearing Coal and Its Influence Mechanism Analysis

Abstract：For studying influence mechanism on permeability of gas-bearing coal,by triaxial servo-controlled seepage equipment for thermo-fluid-solid coupling of gas-bearing coal,coal is measured in different effective stress,temperature and gas pressure based on Darcy＇s Law.The results show that,when temperature and gas pressure is constant,permeability is decreasing with effective stress increasing and the decreasing trend is gradually slowdown;when gas pressure and effective stress is constant,permeability is decreasing with temperature increasing and the decreasing trend is with little effective stress varying;when temperature and effective stress is constant,permeability is first rapidly decreasing then gradually slowing with gas pressure increasing and it shows obviously Klinkenberg＇s effect.It is analyzed on the basis of the results that effective stress,temperature and gas pressure is respective effect of permeability of gas-bearing coal,and the research achievement will provide supporting in theory for increasing gas drainage efficiency and preventing coal and gas outburst.