摘要
基于工作面采动覆岩裂隙分布的微震监测结果,分析了微震事件分布与采动覆岩破裂的关系,采用经验公式和现场矿压监测结果,对比研究了采动覆岩裂隙分布特征。结果表明：沿竖直方向,微震事件在距离煤层0~40 m为高密度分布,在40~70 m内中密度分布,70 m以上为低密度分布;沿工作面倾斜方向,微震事件集中分布于3个区域,分别为机头区域Ⅰ、工作面45~90 m区域Ⅱ和90~120 m区域Ⅲ;基于微震监测推断得到的采动裂隙带高度（工作面煤层上方20~70 m范围）,与基于经验公式得到的采动裂隙带高度约为80 m基本吻合;随工作面推进,微震事件能量具有周期性分布特点,周期步距平均为30 m,与支架工作阻力揭示的周期来压步距吻合。研究成果为采动覆岩裂隙分布特征研究和应用提供了一种监测方法。
Based on the microseismic monitoring and measuring results of the fracture distribution in the mining overburden strata above the coal mining face,the paper analyzed the relationship between the microseismic events distribution and mining- induced fracture in strata.The empirical formula and the site mine strata pressure monitoring and measuring results were applied to the comparison study on the fracture distribution features of the mining overburden strata. The results showed that along the vertical direction,the microseismic events occurred with a distance of 0 ~ 40 m to the seam was distributed in a high density,the microseismic events with a distance of 40 ~ 70 m to the seam was distributed in a medium density and the microseismic events with a distance over 70 m was distributed in a low density. Along the inclination direction of the coal mining face,the microseismic events was concentrated and distributed in three areas and they were the conveyor head area Ⅰ,45 ~ 90 m area Ⅱ of the coal mining face and 90 ~ 120 m area Ⅲ of the coal mining face. Based on the height（ 20~ 70 m above the seam of the coal mining face） of the water conducted zone obtained from the microseismic monitoring result,based on the height of the water conducted zone obtained from the empirical formula was 80 m and could be basically fit. With the advancing forward of the coal mining face,the energy of the microseismic events would have periodical distribution features,the periodical step distance of the microseismic events was 30 m in average and could be fitted with periodic weighting revealed by the working resistance of the powered support. The study achievement could provide a monitoring and measuring method to the study and application on the fracture distribution features of the mining overburden strata.
出处
《煤炭科学技术》
CAS
北大核心
2016年第1期109-113,143,共6页
Coal Science and Technology
基金
"十二五"国家科技重大专项资助项目(2011ZX05040-002-004)
国家自然科学基金青年基金资助项目(51304117
51404140)
关键词
微震监测
采动覆岩裂隙分布特征
裂隙带高度
支架工作阻力
microseismic monitoring and measuring
fracture distribution features in mining overburden strata
height of fracture zone
working resistance of powered support
