煤样粒径对煤与瓦斯突出影响的试验研究

 煤与瓦斯突出是发生在煤矿井下生产中的一种极其复杂的地质动力现象，严重威胁着煤矿安全生产。以由不同煤粉粒径压制而成的型煤为研究对象，采用偏光分析软件、应变控制式三轴仪，对型煤物理力学性质进行研究。并在此基础之上，应用煤与瓦斯突出模拟试验台进行不同粒径条件下的煤与瓦斯突出模拟试验，以探索研究煤粉粒径对煤与瓦斯突出特性的影响规律。研究结果表明，煤样粒径影响型煤的物理力学性质进而对煤与瓦斯突出产生明显的影响效果。具体表现在：煤样粒径越小，型煤表面孔隙结构的分形维数越大，其对瓦斯的吸附特性越好，同时其力学强度也越高；突出模拟试验表明，煤样粒径越小，煤与瓦斯突出发生的强度越大，吸附过程中吸附的瓦斯量也越大，但是煤与瓦斯突出过程中的破碎效果则越不明显。

EXPERIMENTAL RESEARCH ON INFLUENCE OF PARTICLE DIAMETER ON COAL AND GAS OUTBURST

The coal and gas outburst，which threatens coal mine safety production，is an extremely complex geological phenomenon that occurs in the coal mine production. Briquette body of different particle size serves as the object of study，a series of experiments are designed by using the polarization analysis software and strain control triaxial compression apparatus；and the purpose of the study is to get physico-mechanical properties of briquette body with different particle sizes. Further more，coal and gas outburst simulation experiment device is utilized to simulate coal and gas outburst process under the same above-mentioned conditions for the sake of the influence law of different particle diameters on coal and gas outburst. The results of experiment demonstrate that coal particle size has an obvious effect on physico-mechanical properties of briquette body as well as characteristics of coal and gas outburst. Some concrete manifestations are the smaller the particle size of the briquette body is，the bigger the fractal dimension of pore structure of coal sample is and the better its adsorption property on methane gas is. Meanwhile，the smaller particle size will make the higher strength of resistance to destruction of briquette body. The results also show that the briquette body with smaller particle size offers higher intensity of coal and gas outburst and exhibits more quantity of methane adsorption of coal before outburst；whereas，its crushing effect is proved to be less obvious than that of the briquette body with larger particles.