关键词: 煤体渗透率模型, 采掘扰动, 温度, 耦合损伤, 裂隙应变

Abstract: To study the influence of mining disturbance and temperature on coal permeability in front of the working face, the fracture deformation factors caused by mining stress and temperature were divided into three parts: effective stress, adsorption and thermal expansion. The fracture strain expression was derived from damage mechanics, adsorption theory and thermal stress theory. The expression included the coupling damage effect of disturbance stress and temperature. Furthermore, the permeability model of coal under the influence of mining disturbance and temperature was established. The permeability model was verified and analyzed according to two permeability tests. One was changing temperature and the other was changing the disturbance stress and temperature simultaneously. In addition, the parameter sensitivity was also analyzed. The results show that the model can well represent the evolution process of coal permeability with the mining disturbance and temperature effect. Under the same temperature, permeability increases with the increase of internal swelling ratio. Permeability decreases with the increase of thermal internal swelling ratio. The research results will provide useful reference for the development of coal mining and gas extraction technology.

Key words: coal permeability model, mining disturbance, temperature, coupling damage, fracture strain