煤体失稳破坏过程中的低频磁场变化特征研究  

Low-frequency Magnetic Field Variation Characteristic of Coal-body in Instability Failure Process

作　　者：付玉凯[1,2] 李成武[3] 段昌瑞[4] 杨威[3] 

机构地区：[1]天地科技股份有限公司开采设计事业部,北京100013 [2]煤炭科学研究总院开采设计研究分院,北京100013 [3]中国矿业大学(北京)资源与安全工程学院,北京100083 [4]淮南矿业(集团)有限责任公司,安徽淮南232000

出　　处：《煤矿开采》2014年第4期13-17,76,共6页Coal Mining Technology

基　　金：国家科技支撑计划课题(2012BAB13B02);国家自然科学基金项目(U1261211);淮南矿业集团科研项目计划(HWKY-JT-TS-(2011))

摘　　要：为研究不同加载速率下煤岩体失稳破坏过程中的低频磁场变化特征，以单轴加载试验为基础建立了煤岩失稳破坏低频磁场监测系统，分别以不同加载速率对煤岩体试样进行了加载破坏试验。试验结果表明：接收到的原始低频磁场信号包含有大量的背景噪声，采用HHT时频分析方法中的EMD功能，对信号进行了分解重构，有效地过滤掉了背景噪声，对重构后的信号进行FFT分析，发现低频磁场信号的频率为0～20 Hz；煤岩体失稳过程中产生的低频磁场信号对应于煤岩体的时程压力曲线，并且失稳破坏时，磁场信号最为丰富；不同加载速率下，煤岩体产生的低频磁场信号有明显的不同，随着试样加载速率的增大，低频磁场信号的幅值和能量整体有增大的趋势。In order to research low-frequency magnetic field variation characteristic in coal and rock body instability failure process un -der different loading velocity , loading failure test of coal and rock body was finished .Result showed that received original low-frequency magnetic field signals included much background noise .Applying EMD function of HHT time-frequency analysis to decomposing and re-structuring these signals , background noise was effectively removed .The FFT analysis of restructured signals showed that the frequency of low-frequency magnetic field was 0-20 Hz.Low-frequency magnetic field signal from coal and rock body instability was corresponding to time-pressure curve , and magnetic field signal was most abundant in instability failure process .Under different loading velocities , low-frequency magnetic field signal was obviously different .With loading velocity increasing , amplitude of low-frequency magnetic field signal and energy took on wholly rising tendency .

关 键 词：煤岩体 低频磁场 HHT时频分析法 煤岩动力灾害 

分 类 号：TD326[矿业工程—矿井建设]