振动诱发煤与瓦斯突出的机理

振动是诱发煤与瓦斯突出的重要因素,为此实验研究了振动对瓦斯吸附的作用并从理论上分析了振动对煤体结构的影响,探讨了振动诱发煤与瓦斯突出的机理.结果表明:在振动作用下,煤对瓦斯的吸附量有一定程度的减少,吸附能力降低;振动延长了煤样达到吸附平衡的时间,使吸附平衡压力与未加振动时有所升高,煤样中游离瓦斯增多;振动使煤体内的裂隙增加并扩展,当振动强度达到一定值时煤体内形成较大范围的连通裂隙网;在振动对煤体和瓦斯产生的综合作用下,煤与瓦斯突出的危险性大大增加.

Mechanism of coal and gas bursts caused by vibration

For vibration is an important factor among all influencing factors of coal and gas bursts, gas adsorption experiments of coal were done and crack growth in coal was analyzed under vibration conditions. The mechanism of coal and gas bursts was discussed according to experimental and theoretical results. It is shown that under the action of vibration the gas content of coal and the adsorption ability decrease, and after vibration the time to reach the gas absorption equilibrium in coal and the adsorption equilibrium pressure increase, indicating that vibration makes free gas increase and the gas content of coal reduce. Vibration also leads to the increasing of crack number and crack growth rate, and when the vibration strength arrives at some value a large-scale connected crack network appears. The integrated influence of vibration on the coal and gas system increases the danger of coal and gas bursts.