逆断层下盘不同采高工作面支承应力演化规律研究

Research on evolution law of bearing stress in working face with different mining height in reverse fault footwall

以逆断层下盘不同采高工作面开采为背景,采用UDEC数值模拟方法,研究了下盘工作面向逆断层推进过程中不同采高下支承应力的分布特征及演化规律。研究表明:下盘工作面向逆断层推进过程中,由于逆断层松弛活化产生的阻隔效应,支承应力分布特征发生演化,其峰值呈现先减小后增大的变化趋势,其明显影响范围不断减小。下盘工作面3 m和5 m采高的支承应力演化基本同步,支承应力分布相似;当煤层采高增大为7 m时,受断层采动活化及煤柱的耦合作用影响,支承应力峰值较高,采动影响更为强烈。工作面前方逆断层对支承应力的影响较大,应及时加强工作面及回采巷道支护。

Taking the working face with different mining height in footwall of reverse fault as engineering background,the distribution characteristics and revolution law of bearing stress in footwall face with different mining height during advancing to the reverse fault were studied.The results showed that because of the barrier effect caused by reverse fault relaxation and activation,the distribution of bearing stress changed during the face advancing,the peak of bearing stress decreased first then increased,obvious influence range shrank.The bearing stress evolutions of footwall face with 3 m height and 5 m height were basically synchronous,and the distributions of bearing stress were similar;when the height of face increased to 7 m,the peak of bearing stress was higher and the mining influence was more intense under the influence of fault activation and coupling effect of coal pillar.In front of working face,the influence of reverse fault on bearing stress was greater,so strengthening the supporting in working face and roadway was necessary.