State Key Lab of Coal Resources and Safety Mining.China University of Mining and Technology(Bejing) school of Resources and Safety Engineering,China University of Mining and Technology (Beijing)

由于含瓦斯煤层突出危险性的判别是预防煤与瓦斯突出的关键,因此通过分析煤层开挖现场的应力和瓦斯条件,提出了煤层"真实突出危险性"的定义,认为含瓦斯煤层如不存在瓦斯卸压带,在应力、煤层原始瓦斯压力作用下的稳定性代表了真实的突出危险性。利用RFPA2D-Flow软件和相似模拟试验方法,以煤体强度为分组指标,研究了各组煤体在应力、瓦斯压力作用下的真实突出危险条件。煤层突出的瓦斯压力-应力临界条件可分为3个阶段:1在低水平应力范围内,应力阻碍突出,此阶段发生的突出主要以瓦斯压力作用为主,应力的增加对煤体起加固作用;2随着应力的增加,应力的作用由加固煤体转变为破坏煤体,应力加剧突出;3随着应力继续增加,突出发生的瓦斯压力降低并基本固定在某一水平,不再随应力增加而变化,此时煤体在高应力作用下发生宏观破坏,煤体状态处于峰后阶段,瓦斯压力的作用主要是破坏具有残余强度的煤体并抛出。最后,根据煤体破坏瓦斯压力-应力临界关系方程,得到了利用煤体强度参数确定煤体真实突出危险性的方法。

in order to study the micro pore structure features of the coal mass and the meso defomation law ofthe adsorbed gas loaded coal a low prssure liquidntrogen adsoption and SEM were applied to study the pore type and pore sze distribution of thecoal mass.Aloaded CT scaming deviceof the adsorption gascoal ma5s was researched and developed.The indutrial CT scanning was appied to observe the meo defomation processing ofthe adsoptiongascdl massin the loadingprocess.The results showed that the pore on the coalsuriace would be a cylindrica. narow gap.wedge iniootle type pore and others.According to the comecion ypes of the intenal pore the pores could be divided into atoll w- through hole intenal comected hole,one end closed hole and cosed hole. undest thedfiferent stesscondition.the CT images showed that the cal internal was in inhonogeneityth pore representation was in heterogeneaous distribution features and the loaded falure porein the adsoroedgas coal mass aso woud be in heerogeneous featres. nder the loaded conditon.the adsoption gas coal mass would have a swelling effect and a shrinking effect locally:cenfrllythe presentation would be the swelling effect and was caused due to the muti pore and inhomogeneit .The stuty resulis revealed themicro structure and deformation features of the coal mass which could provide the meso means and studly base to study the falire nechanis nof the gassy coal and outburst disaster dynamic process.

国家自然科学基金面上资助项目(51374096)；河南理工大学博士基金资助项目(SZB2013-17)；