大采高工作面合理煤柱尺寸留设研究

Research on rational coal-pillar dimension preserving on working face with large mining height

针对寺河矿采掘衔接紧张、采区煤柱损失大的问题,通过数值模拟、煤柱受力分析及煤柱强度测试,开展了大采高工作面合理煤柱尺寸留设研究,结果表明：煤柱宽为35 m时,巷道围岩变形量小,受压小,为较合理的煤柱尺寸;对煤柱强度进行测试可得,W13012巷和W13013巷之间煤柱煤体强度值大部分集中在10-20 MPa,煤体强度平均为16.05 MPa,煤体中等硬度,煤柱浅部强度值普遍小于深部强度值;对煤柱受力进行分析,在受超前压力影响期间,距巷道表面较近的煤体逐渐被压裂破坏,而经过煤柱的峰值点后,煤柱在受超前压力期间和滞后压力期间受力基本恒定,煤柱应力只有一个峰值且峰值位置右侧1 m范围内应力均达到自身极大值,说明在此支护强度下此煤柱宽度的4倍宽度是极限的煤柱宽度。

In view of the mining cohesion tension in Sihe Coal Mine,and mining area coal pillar loss is big,through numerical simulation,the stress analysis of coal pillar and the coal pillar strength test,the authors have studied the rational coal-pillar dimension on large-mining-height face,the results indicate： when the size of coal pillar is 35 m,the deformation of roadway surrounding rock and pressure are small,it is a more reasonable size of coal pillar. It gets that the strength between W13012 and W13013 lane pillars is mostly in10 - 20 MPa through testing the strength of coal pillar. The average strength is 16. 05 MPa,coal＇s hardness is moderate,and the shallow coal pillar strength value is less than deep intensity value. Analyzing the stress distribution of coal pillar during the period of affected by stress in advance,it shows that,the coal close to the roadway＇s surface is gradually destroyed,and after the peak point of coal pillar,the pillar＇s pressure is basically constant when it bears advance pressure and lag pressure,the coal pilar＇s stress has only one peak value,and this peak value exist in the range of 1 meter in the right side where it occurs,it was shown that 4 times of coal pillar＇s width is the limit width of coal pillar.