| To exploit methane resources, prevent from the occurrence of the mine gas accident by the root at the same time and protect the atmosphere environment are ideal target that the people pursue. The methane-coalbed coupling movement theory researches the mutual action law among the framework deformation of porous media, the adsorptive deformation of grain, the diffusion-desorption of adsorbed fluid, and free fluid seepage, so that scientific basis is provided for the decision to exploit methane, prevent and control mine gas and in other engineering application. Most of gas (methane) in the coalbed is adsorbed state. Because its mechanical function and movement forms differ from the free gas in coalbed, Terzaghi's effective stress principle in free fluid-solid system cannot be adapted to adsorbed methane-coal system. Therefore, the gas-solid coupling movement theory with adsorption is studied in this dissertation. The most researches are given as the follows:(1) A series of physical concepts or models are put forward or revised in this thesis by discussing the structure of coalbed, the existence form of the methane in coalbed, the diffusion and seepage of methane, coalbed deformation and theirs correlations, such as the common structure mode of methane-coal, the methane movement mode, coalbed deformation mode, adsorptive swelling mode. According to the physical models put forwards and the moistened length in cross-section as adsorbed by porous media, the surface physico-chemistry and elastic mechanics, the coupling formulas of the adsorptive swelling stress and strain, effective stress, porosity and permeability are derived. The theoretical calculation result is in accordance with the experimental and numerical simulation results.(2) The differential equations of the complete coupling movements that are the solid coal deformation, the adsorbed methane diffusion-desorption, the free methane seepage flow are built up; the differential equations (equation) of the non-coupling...
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