Temperature affected to coal deformation and permeability in gas drainage during pressure declining process

Taking K2 seam in Chongqing Songzao Mine as a study object,a self-developed gas content coal thermo-fluid-solid coupling triaxial servo seepage test devi ce was applied to the seepage test of the gas content coal in the gas pressure declining process under the condition of different temperature and to analyze the temperatur e in the drainage pressure declining process affected to the gas content coal specimen deformation and permeability.The results showed that during the gas pressure decli ning process,the axial strain would be decreased firstly with the temperature increased and then would be steadily increased and the radial strain would be steadily develo ped forward to the negative value direction with the temperature increased.Under each temperature condition,the permeability of the gas content coal would be decreased f irstly with the gas pressure reduced and then would be in an increasing tendency. During the drainage pressure declining process,the permeability of the coal sample with t he variation of the temperature,would have a relevant relationship to the strain with the temperature varied.