煤样破裂表面电位多重分形特征  

Multi-fractal characteristics of surface potential of coal during the fracture

作　　者：刘杰[1,2] 王恩元[1,2] 李忠辉[1,2] 马衍坤[3] 

机构地区：[1]中国矿业大学安全工程学院,江苏徐州221008 [2]中国矿业大学煤矿瓦斯与火灾防治教育部重点实验室,江苏徐州221008 [3]安徽理工大学能源与安全学院,安徽淮南232001

出　　处：《煤炭学报》2013年第9期1616-1620,共5页Journal of China Coal Society

基　　金：十二五”国家科技支撑计划资助项目(2012BAK04B07-2);国家自然科学青年基金资助项目(40904028);全国博士学位论文作者专项资金资助项目(201055)

摘　　要：为深入分析煤样受载破裂机制,试验研究了煤样单轴压缩下表面电位变化规律,应用多重分形统计理论分析表面电位信号,计算其多重分形谱,并分析多重分形谱特征参数随加载过程的变化规律。研究结果表明:煤样表面电位信号存在多重分形特征,在较大尺度内满足标度不变性;不同尺寸的试样,表面电位信号多重分形谱呈右钩状;多重分形谱特征参数Δα和Δf的变化规律与试样受载变形破裂过程具有良好的对应关系,Δα和Δf经过较长时间平稳升高后迅速下降的趋势改变可以作为破裂的前兆信息,对试样失稳进行提前预警。In order to analyze the failure mechanism of coal under the load, muhi-fractal characteristics of surface po- tential of coal sample under uniaxial compression was studied. The surface potential was analyzed using muhi-fractal theory to calculate the muhi-fractal spectrum. The change rules of characteristic parameters of muhi-fraetal spectrum with the loading process were studied. The results show that the surface potential represents multi-fractal feature, and keeps scale invarianee in the wide range. The shape of the muhi-fractal spectrum of different size specimens shows right hook. The characteristic parameters of muhi-fraetal spectrum, Aa and A f, vary with the process of deformation and fracture of coal sample with load. The changes of trend that Act and Af increase in a long time, then decrease rap- idly can be used as a precursory factor of coal-rock failure to forecast the instability of the samples. The results are helpful to understand the inherent law in the coal specimen failure process and forecast the dynamic disaster using the potential.

关 键 词：表面电位 时间序列 多重分形谱 特征参数 

分 类 号：P631.3[天文地球—地质矿产勘探]