煤岩突出中单个煤壳失稳前兆阶段的能量分析

在不计突出前兆阶段煤壳动能的条件下，建立了地应力、瓦斯压力与渗流耦合作用下孔隙介质球对称力平衡方程；根据球对称性质使弹性与塑性阶段应变Lode参数相同，满足单一曲线的物理关系条件，将单轴本构模型推广，得到煤壳中应力强度 与应变强度 之间的物理关系式；求得煤壳弹、塑性区径向位移 的表达式，并发现其可分解为相应偏应变的位移 与平均应变的位移 。综合运用几何方程、力平衡方程、几何方程和应力强度与平均应力的关系，对突出前煤壳进行的能量分析表明：煤壳位移、形变时的外力功变化可分解为相应偏应力、平均应力和渗流力的外力功 ， ， ，它们分别与煤壳偏应力应变能、体积应变能和孔隙体积能的变化的 ， ， 相对应，得到三个功、能增量关系的研究结果。为建立单个煤壳失稳的突变模型，对地应力、瓦斯压力与煤介质三因素在煤壳解体、瓦斯膨胀内能释放及高压瓦斯流对碎煤喷射的突出过程进行研究提供了基础。

Energy analysis of premonitory phase of outburst of a single coal shell in coal-rock outburst

On the condition that the kinetic energy of coal shell in premonitory phase of its outburst is ignored; the equilibrium equation of spherical symmetric force of pore medium is established, which is under the coupling action of ground stages, gas pressure and effluent seepage. The character of spherical symmetry makes the strain Lode parameter at elastic and plastic stages is the same, and meet the condition of the physical relation of single curve. Popularized the uniaxial constitutive model, it can be educed that the relational expression between stress intensity and strain intensity of coal shell. It is discovered that, the educed expression of radial displacement u in elastic and plastic zones of coal shell, can be broken down into the displacement corresponding to deviatoric strain and the displacement corresponding to average strain. The energy analysis, which is carried through by using geometry equation, force equilibrium equation, physical equation and the relation of stress intensity and average stress synthetically, shows that the external force work change can be broken down into the external force work , and corresponding to deviatoric stress, mean stress and seepage stress; they are respectively corresponding to changes of strain energy of deviatoric stress, volumetric strain energy and pore volume energy; i.e. , . and The findings of two work-energy increment equilibrium relationship can be educed. It builds up the foundation for engaging catastrophe theory analysis of disintegration and outburst of a single coal shell in the outburst process.