两软一硬煤层突出控制因素与发生规律

针对两软一硬煤层特殊的瓦斯地质条件,以云盖山井田一矿二1煤层为例,探寻了两软一硬煤层煤与瓦斯突出的控制因素,分析了掘进工作面掘进期间突出预测指标的分布特征,总结归纳了"两软一硬"煤层煤与瓦斯突出发生规律.研究结果表明,由于地质构造变动,云盖山一矿二1煤层产状变化较大,煤层倾角发生急剧变化的地带,地应力集中;受层间滑动构造的影响,煤层厚度变化较大,具有突然增厚、变薄以至尖灭、挤灭现象;二1煤层构造软煤呈连续层状发育.因此,在煤层薄、厚交接处(煤层急剧变化带),小断层附近,应力集中,瓦斯积聚,煤体破坏严重,易发生突出.此项研究,可为地质条件类似矿井开展瓦斯地质研究和瓦斯灾害防治工作提供方法借鉴和理论指导.

Control factors and occurrence regularity on coal and gas outburst of two-soft and one-hard coalbed

For the gas geological conditions on a two-soft and one-hard coalbed,the Ⅱ1 coalbed in Yungai mountain coalfield was taken as an example.The control factors of the coal and gas outbursts on a two-soft and one-hard coalbed were explored,and the distribution characteristics of prediction index on coal and gas outburst were analyzed during the heading face boring course.By the base,the research was supported by the occurrence regularity of the coal and gas outburst on a two-soft and one-hard coalbed.The results show that the ground stress is concentrated in the dramatic changing zone of seam inclination due to the changes in the geological structure.Because of an interlayer sliding structure,the coal seam thickness varies largely with the phenomenon of a sudden thickening and thinning as well as tip-off and squeeze off.And the deformed coal is a continuous layer distributed in the Ⅱ1 coalbed.Thusly,the coal and gas outburst will be readily happen in the junction of thin and thick coalbeds and near the small faults.The study can provide the methods and theoretical guidance on gas geological research and gas disaster prevention work for the mine with similar geological conditions.