煤岩破裂全过程的声发射序列分形特征研究

Study on Fractal Characteristics of AE Sequence of Whole Process of Fracture of Coal or Rock

为获得煤矿巷道内某点煤岩体的稳定性信息,在不同应力水平下,对煤岩和煤进行单轴加压破坏全过程的声发射(AE)试验,将收集的煤岩AE信号在时间分布上进行分形特征研究。在此基础上,提出"分形同测"思想,即煤矿巷道内某点可能为煤岩和煤的混合体,两者的AE信号频率不同,同时采集两者的AE事件数,利用分形理论来预测其稳定性。结果表明:关联分维值D的变化能很好地反映煤岩内部微破裂的发展及演化情况。

In order to obtain information on stability of coal and rock at a point, the paper studies acous- tic emission time distribution characteristics for the destruction of whole process of coal rock or coal under different stress level. The paper proposes fractal with test thinking to improve the prediction accuracy. In other words, the thinking is that a certain point may be coal rock and coal mixture, according to two acoustic emission signal frequencies, the number of coal rock AE events and that of coal AE events can be obtained at the same time, and stability of point can be predicted using the fractal theory. Research results show that changes in correlation fractal dimension D can well reflect micro-fractures in coal rock.