水力卸压防止承压散体煤和瓦斯突出机理

从散体煤和瓦斯失控突出条件出发，分析了超前水力卸压防止散体煤和瓦斯突出作用原理，并通过检测水力卸压前后瓦斯涌出量变化、利用电磁辐射技术检测煤体破裂变形以及相关实际资料验证了该机理的正确性。结果表明，实施水力卸压防突措施时电磁辐射强度及脉冲数增大，有利于防止突出，其防突作用原理有3条：1）煤体增裂预释放瓦斯，增加切向应力和散体摩擦阻力，2）增加煤体位移，预降低高压侧径向有效地应力，减少散体突变运动径向应力差，3）注水湿润使散体间及相邻蝶岩体黏结，增大了散体摩擦阻力系数．

Mechanism of Preventing Coal and Gas Compression Disseminated Values Outburst with Stress Pre-Released Hydraulically

Based on the conditions of coal and gas outburst,the action mechanism for preventing coal and gas compression disseminated values outburst with stress pre-released hydraulically was analyzed,the accuracy of this mechanism was validated by measuring the gas emission before and after pre-releasing stress hydraulically,measuring the rupture failure by the electromagnetic radiation technique and the correlative practical datum.The results show that the electromagnetic radiation intensity and pulse count are increscent when taking the measure of stress pre-released hydraulically,which is propitious to prevent the coal and gas outburst.The action mechanism consists of three aspects: 1) Pre-releaseing gas and increasing tangential stress and disseminated values friction resistance;2) Pre-releaseing the radial effective geo-stress on high-tension side and reducing the radial stress difference of disseminated values chop motion for enhancing coal displacement;3) Making the disseminated values and adjacent coal and rock felting by flooding water and increasing the disseminated values' friction resistance coefficients.