不同形式载荷煤体渗透率及其损伤试验研究

Experiment research on coal permeability and damage under different type load

通过试验测定煤体分别在不同轴压和围压加、卸载状态下的渗透率,并对试验结果进行拟合。结果表明,在加、卸载过程中,煤体渗透率随轴压呈负幂函数规律减小,随围压呈负指数规律减小;渗透率随围压的变化幅度远大于轴压,围压卸载后煤体渗透率恢复程度远小于轴压;轴压和围压加、卸压过程煤体渗透率不可逆,出现渗透率损伤。

With the experiment, coal seam was measured on the permeability individually under the conditions of the different axial pressure and surrounding pressure loading and unloading and the experiment results were fitted. The results showed that during the loading and unloading procedures, the permeability rate of the coal seam would be reduced with the axial pressure being the negative power law and could be reduced with the surrounding pressure being the negative index law. The permeability rate of the coal seam would be higher than the axial pressure with the variation extent of the surrounding pressure and The recovery degree of the permeability rate of the coal seam would be lower than the axial pressure after the surrounding pressure unloaded. During the loading and unloading procedures of the axial pressure and surrounding pressure, the permeability rate of the coal seam would be irreversible and the permeability rate would be damaged.