突出煤渗透特性与应力耦合试验研究

 根据常规三轴具有突出倾向型煤的瓦斯渗流试验所获得的瓦斯渗流速度–围压和瓦斯渗流速度–轴压关系，分析具有突出倾向型煤中的瓦斯渗流速度变化与应力的耦合关系，建立一定瓦斯压力下瓦斯渗流速度与围压、轴压的关系式，建立应力–渗透系数方程。结果表明：瓦斯压力和轴压一定时，瓦斯渗流速度随着围压的升高逐渐降低，为二阶曲线关系；当瓦斯压力和围压一定时，瓦斯在型煤中的渗流速度随着轴压的升高呈四阶曲线关系，且型煤破坏后的瓦斯渗流速度大于型煤起始渗流速度。基于试验结果，提出瓦斯渗流困难应力点这一特征值，该参数对预防煤与瓦斯突出事故、提高瓦斯抽采效率具有一定意义。

TEST STUDY ON COUPLING RELATIONSHIP BETWEEN PERMEABILITY CHARACTERISTICS AND STRESS OF OUTBURST COAL

Based on the relationships of gas seepage speed with confining pressure and axial compression which are obtained by conventional triaxial test of gas seepage of outburst coal,the coupling relationship between the gas seepage speed and stress of outburst coal is discussed,and the relationships of gas seepage speed with confining pressure and axial compression with certain gas pressure are established and so is the equation of stress with seepage coefficients. The following results can be drawn. When the gas pressure and axial compression are determined,the gas seepage speed decreases as confining pressure increasing with the relationship of second-order curve relationship. When the gas pressure and confining pressure are determined,the relationship between the gas seepage speed and axial compression is fourth-order curve relationship,and the gas seepage speed of broken Briquette is larger than initial speed. A characteristic parameter,difficulty stress point of gas seepage,is proposed,which is useful for prevention of accidents of coal and gas Dutburst.