摘要
通过建立受载煤体电阻率-声发射实时监测系统,测试并研究了煤岩单轴压缩破坏过程中电阻率的实时变化规律,并对产生这种变化的原因进行了分析。结果表明:煤岩体电阻率变化主要取决于内部裂隙的形成、扩展与闭合。煤岩在加载过程中,以约0.4倍的极限载荷Fm为界,电阻率随着载荷的增加呈现先减小后增加的趋势,在F>0.7Fm时,煤岩体电阻率剧烈增加,并在失稳时达到峰值,之后电阻率波动降低。在煤岩体损伤活跃阶段,电阻率与载荷具有较好相关性,相关系数在0.95以上,在稳定性方面有一定的优越性。煤岩在受载过程中的电阻率变化可以反映煤岩载荷与破裂的变化,电阻率在应力峰值前的突然增大可以作为煤岩破裂的一个前兆特征,利用电阻率监测煤岩破坏变形,可以为煤岩动力灾害监测预警提供一种新的思路。
By resistivity and acoustic emission realtime monitoring system established for Loaded coal rock,the resistivity variation is tested during the failure process of coal rock,and the reason for this change is analyzed. The results show that:the coal rock resistivity change primarily depends on the expansion or closure of internal cracks. As a load profession of about 0. 4 Fm,the resistivity increases first and then decreases,once F〉 0. 7Fm,the coal rock resistivity will increase dramatically,and it peaks at destabilization and reduces volatility after it. In the active phase of coal rock damage,resistivity has a good correlation with load,the correlation coefficient between the two parameters is always above 0. 95,and it shows a superiority to the acoustic emission in terms of stability. Changes of resistivity during the process of fracturing can reflect the change of fracture and load,a sudden resistivity increase can be used as a precursor to a fracture of coal rock,the use of coal rock resistivity monitoring provides a new idea to monitor coal rock dynamic disasters.
出处
《世界科技研究与发展》
CSCD
2016年第2期245-248,共4页
World Sci-Tech R&D
基金
大型油气田及煤层气开发国家科技重大专项(2008ZX05041-002)资助
关键词
煤岩
破裂
电阻率
相关性
声发射
coal rock
fracture
resistivity
correlation
acoustic emission