保护层开采保护范围的极限瓦斯压力判别准则

针对传统的保护层开采保护范围的残余瓦斯压力判别准则在实际应用中的局限性，结合某煤矿上保护层开采工程，提出了一种新的保护层开采保护范围的极限瓦斯压力判别准则。根据煤与瓦斯突出的固气耦合失稳理论，通过引入煤体孔隙率与渗透率的动态变化模型，建立了有限变形下煤与瓦斯突出的固气动态耦合失稳模型；针对该工程实例，得到了被保护层发生煤与瓦斯突出的极限瓦斯压力值，从而建立了以极限瓦斯压力值为判定值的保护层开采保护范围的判别准则。研究结果表明，该工程的保护层开采保护范围的极限瓦斯压力判别准则的判定值为0.25 MPa，该准则反映了地应力、瓦斯压力与煤的结构对煤与瓦斯突出的综合作用。

Discrimination Criterion of Ultimate Gas Pressure of Protection Region for Exploiting Protective Layer

Aimed at the limitations of applying the traditional discrimination criterion of protection region for exploiting protective layer based on the remain gas pressure in practice, as a coal mine exploiting upper-protective layer an project example, a new discrimination criterion of ultimate gas pressure of protection region for exploiting protective layer was brought forward . According to the instability theory of coal and gas outburst coupled solid and gas, the instability dynamic model of coal and gas outburst coupled solid and gas under finite deformation was founded by introducing the dynamic changing model of porosity and permeability of coal with low permeability. Integrating the practical conditions of this coal mine, the ultimate gas pressure of coal and gas outburst was obtained; sequentially the discrimination criterion of protection region of protected layer was established that its discriminating value was the ultimate gas pressure. The investigation results show that the discriminating value for discrimination criterion of ultimate gas pressure of protection region for exploiting protective layer in this coal mine is 0.25MPa, and this new discrimination criterion reflects the effect of stress, methane gas pressure and the structure of coal on the coal and gas outburst, sequentially assures more comprehensive consideration.