School of Mechanics and Engineering, Liaoning Technical University
School of Physics, Liaoning University

随着开采深度和强度增加，煤与瓦斯突出动力灾害频发，冲击力致灾机制成为目前研究的主要方向。为进一步揭示高地应力条件煤与瓦斯突出冲击力演化规律及破坏机制，采用自主研发的煤与瓦斯突出全过程模拟巷道系统，引入冲击力和声发射监测技术，以45%CO2和55%N2混合气体压力模拟煤层瓦斯压力，以轴压模拟上覆岩层应力作用，围压模拟围岩应力作用，以平煤十一矿突出煤层为研究对象，考虑埋深为600、800、1 000、1 200、1 400和1 600 m的地应力条件，进行了煤与瓦斯突出模拟试验，分析了煤−瓦斯两相流运移过程、煤粉分布及冲击力演化特征，得到了瓦斯压力、临界瓦斯压力、试验有效应力、声发射信号与冲击力之间的影响关系规律，从煤与瓦斯突出能量转化角度分析了瓦斯内能向冲击动能，即瓦斯压力向冲击力转化特征。研究结果表明：①突出孕育阶段受力情况及破坏程度影响突出发生后冲击力在巷道内传播特性，随模拟埋深增加，冲击力演化特征愈发复杂，具有明显脉冲特征，且随脉冲特征出现冲击力升高。②脉冲特征划分为高频阶段和低频阶段，高频阶段煤−瓦斯两相流速度快、强度高、突出危险性强；低频阶段危险性随突出发展进程逐渐减弱。③突出两相流动能主要由瓦斯内能提供，部分瓦斯压力转化成冲击力，冲击力强弱主要由瓦斯压力决定，在高地应力作用下，深部煤体相对浅部更易发生煤与瓦斯突出。④突出开始时，声发射振铃计数峰值点早于冲击力峰值点，声发射信号更早监测到突出危险性，但冲击力更能具象反映煤体破裂情况，声发射振铃计数出现陡增时，伴随脉冲特征出现，但脉冲特征出现不一定对应声发射振铃计数陡增。

With the increase of mining depth and intensity, the dynamic disaster of coal and gas outburst was frequent. The disaster-causing mechanism of impact force has become the main direction of current research. In order to further reveal the impact force evolution law and failure mechanism of coal and gas outburst under high ground stress. The self-developed simulation roadway system in the whole process of coal and gas outburst was adopted, and the monitoring technology of impact force and acoustic emission were introduced. The gas pressure in coal seam was simulated by mixture pressure of 45% CO2 and 55% N2. The stress of overlying strata and surrounding rock was simulated by axial and confining stress, respectively. Taking the outburst coal seam of Pingding shan No.11 mine as the research object to conduct the simulation test of coal and gas outburst. The ground stress with buried depths of 600 m, 800 m, 1 000 m, 1 200 m, 1 400 m and 1 600 m were considered. The migration process of coal-gas two-phase flow, distribution of pulverized coal and evolution characteristics of impact force were analyzed. The influence between impact force and gas pressure, critical gas pressure, effective stress of test, acoustic emission signal were obtained, respectively. Transformation characteristics of gas internal energy to impact kinetic energy, i.e., gas pressure to impact force, was analyzed from the viewpoint of energy conversion of coal and gas outburst. The results shown that, (1) The force condition and damage degree in embryonic stage of outburst affected the propagation characteristics of impact force in the roadway after outburst. As the simulated buried depth increased, the impact force evolution became more complex, accompanied by obvious pulse characteristics, and the impact force value increased with the pulse characteristics. (2) The pulse characteristics was divided into the stage of high and low frequency. Coal-gas two-phase flow in high frequency stage had the characteristics of rapid speed, high strength and strong outburst hazard. The outburst hazard in low frequency stage gradually weakened with the development of outburst. (3) The two-phase flow energy of outburst was mainly from gas internal energy. Part of gas pressure was converted into impact force. The strength of impact force was mainly determined by gas pressure. Deep coal, with high ground stress, was more prone to coal and gas outburst than shallow one. (4) At the beginning of outburst, the peak point of acoustic emission ringing count preceded that of impact force, i.e., the acoustic emission signal detected outburst hazard earlier. But the impact force was more specific to coal fracture. A steep increase in acoustic emission ringing count was accompanied by pulse characteristics. However, the appearance of the pulse characteristic did not necessarily correspond to a steep increase in acoustic emission ringing count.

国家自然科学基金面上资助项目(51874165)；辽宁省“兴辽英才计划”资助项目(XLYC1902106)

唐巨鹏，任凌冉，潘一山，等. 高地应力条件煤与瓦斯突出冲击力演化规律研究[J]. 煤炭科学技术，2023，51（8）：116−128

TANG Jupeng，REN Lingran，PAN Yishan，et al. Study on the impact force evolution law of coal and gas outburst under high ground stress[J]. Coal Science and Technology，2023，51（8）：116−128