煤体冲击破坏超低频/极低频电磁异常特征分析  

Characteristic analysis of SLF /ELF electromagnetic anomaly in the process of coal impact damage

作　　者：李成武[1] 杨威[1] 徐晓萌[1] 王启飞[1] 

机构地区：[1]中国矿业大学(北京)资源与安全工程学院,北京100083

出　　处：《煤炭学报》2014年第10期2014-2021,共8页Journal of China Coal Society

基　　金：国家自然科学基金资助项目(51274206);国家重点实验室开放课题资助项目(SKLCRSM11KFB02)

摘　　要：为确定煤体冲击破坏过程中是否产生超低频/极低频电磁信号,利用分离式霍普金森压杆（SHPB）实验系统和ZDKT-1型瞬变磁振测试系统,研究不同冲击速度下煤体破裂电磁信号变化规律。通过分析电磁异常信号的Hilbert时频谱特征,确定煤体冲击破坏下的超低频/极低频电磁效应,研究不同冲击速度下电磁信号能量和冲击耗散能之间的关系。结果表明：煤材料在冲击破坏过程中能产生超低频/极低频电磁信号,信号主频在0～30 Hz;电磁信号幅值和冲击速度呈现正线性相关,电磁信号能量和冲击速度为二次多项式关系,冲击耗散能和电磁能增长趋势基本相同,超低频/极低频电磁信号强度可间接反映煤体内部损伤的程度。In order to determine whether the impact damage of coal produces SLF/ELF electromagnetic signal in the process of coal and rock dynamic disasters, the change law of electromagnetic signal under different impact speed was studied using Split Hopkinson Pressure Bar （SHPB） experimental system and ZDKT-1 transient magnetic field test system. Subsequently, the Hilbert spectrum signature of abnormal electromagnetic signal was analyzed and the SLF/ ELF electromagnetic effect in the process of coal impact damage was confirmed. In addition, the relationship between the impact dissipation energy and the energy of electromagnetic anomaly was studied. Results show that there is SLF/ ELF electromagnetic signal in the impact damage process of coal body, and the dominant frequency of electromagnetic anomaly is 0-30 Hz. Furthermore, the amplitude of electromagnetic signal has positive linear correlation with impact velocity, and the relationship between the energy of electromagnetic signals and the impact velocity is quadratic polyno- mial. Impact dissipation energy and electromagnetic energy have same rising trend with the increase of impact velocity. Therefore,the internal damage of coal can be described by the strength of SLF/ELF electromagnetic signal.

关 键 词：煤体 SHPB 冲击破坏 超低频/极低频 电磁异常 

分 类 号：TD324[矿业工程—矿井建设]