三维应力下煤与瓦斯突出模拟试验研究

 煤与瓦斯突出实质是开采扰动下含瓦斯煤体在三维应力作用下突然发生的力学失稳破坏，严重威胁着煤矿安全生产。以典型高瓦斯矿井-阜新孙家湾煤矿突出煤粉压制而成的型煤为研究对象，利用自主研制的煤与瓦斯突出仪，进行煤层埋深－600 m，在轴压、围压、孔隙压三维应力条件下煤与瓦斯突出模拟试验，以探求煤与瓦斯突出规律。试验再现煤与瓦斯突出孔洞口小腔大、突出煤粉分布具有分选性等突出特征现象，验证煤与瓦斯突出模拟仪的可靠性。通过对试验结果分析，划分6个突出区域，得到以下新认识：突出煤粉质量分布具有区域性特征，存在煤粉质量极值区和均值区。突出试验现象表现为瓦斯–煤气固两相射流特征，为引入射流理论研究煤与瓦斯突出机制提供新思路。突出煤粉量极大值区域位于突出中远区，是瓦斯–煤气固两相射流突出破坏能量的耗散阶段区域。不同粒径突出煤粉分布具有明显的波动分布特性。煤粉质量极大值区以较小粒径煤粉为主，煤粉质量极小值区以较大粒径煤粉为主，突出末端区域以较小粒径煤粉为主。指出高压瓦斯是突出发生的动力源和煤体粉碎粉化的破坏源，煤与瓦斯突出能量释放具有波动性特征。试验结论对煤与瓦斯突出的机制认识具有重要参考价值。

EXPERIMENTAL STUDY OF COAL AND GAS OUTBURST UNDER TRIDIMENSIONAL STRESSES

In fact，coal and gas outburst is mechanical destabilization and damage to gassy coal induced by mining under tridimensional stresses，seriously threatening safe production for coal mine. Taking the moulding coal powders of typical high-gassy coal mines，Sunjiawan coal mines in Fuxin as research object，the experiments of coal and gas outburst were made to detect rule by home-made device under tridimensional stresses including axial pressure，confining pressure and pore pressure to simulate －600 m mining. The outburst features were reproduced such as that the size of jet mouth is smaller than the radius of jet hole and the distribution of jet coal powders has sorting feature. The reliability of device was verified. According to the results，six outburst zones were divided and new understandings were presented. The mass distribution of coal powders had zone feature and existed extremal zone and mean zone. A new idea was presented to study outburst mechanism based on the jet features of gas-coal two-phase reflected in experiments. The maximum zone of mass of coal powders was located in medium long zone which was the energy dissipation zone of jet outburst of gas-solid two-phase gassy coal. The remarkable wave character was observed by the distribution of coal powders on different particle sizes. The coal powders of smaller size were main part in maximum zone of mass. The coal powders of rather large size were main part in minimum zone of mass. The coal powders of smaller size were main part in the ending of outbursting zone. It was presented that high-pressure gas is not only outbursting power but also damage power for powdered coal. The energy releasing has wave character in the process of coal and gas outburst. The conclusions can offer references to mechanism understanding of coal and gas outburst.