Study On Fractal Characteristics Of Ae Sequence Of The Whole Process Of The Fracture Of Coal Or Rock

Coal and other solid materials in the destruction of rock deformation process is accompanied by acoustic emission and methane gas. so based on the acoustic emission signal monitoring can be realized to the coal and rock material of internal damage detection, Also can realize gas prediction. With the development of science and technology, it can take advantage of the acoustic emission technique for real-time monitoring of coal and rock material failure process to find the location of the crack, nature and severity. The location of the acoustic emission events is material or structure partial damage or deformation and local area, The location of the acoustic emission energy release rate is intrinsically linked with the degree of injury. Acoustic emission detection technology advantage is more prominent than the traditional nondestructive testing. It is not sensitive to the geometry of the object to be detected. It also can be achieved for real-time diagnostics and dynamic assessment. At the same time, it contains a lot of important information, such as the location of the micro fracture, patterns, and energy release rate. However, because of the complexity of the acoustic emission signals, nonlinear and non-stationary, Therefore, the traditional signal analysis method and theory will make the error increases the signal processing to limit the application of acoustic emission technology research. This paper uses the fractal theory to processes and analysis for the acoustic emission signal obtained to obtain the ae source location information, so it has very important theoretical significance and practical value.Based on fractal theory to optimize, the paper uses matlab to simulate data. Through to the coal and rock acoustic emission signal event time series analysis under different load stress. Then study the change of coal and rock correlation dimension under different damage stages, Its main content is as follows:(1) In this paper, the acoustic emission in the process of different stress load time series is studied, such as fractal theory and fractal dimension algorithm, calculate the correlation dimension and coal rock.(2) Through the coal samples acoustic emission experiments of different stress levels to study the fractal characteristics of acoustic emission in the time distribution.(3)Through the analysis between the acoustic emission events rate of coal and rock samples and the connection correlation dimension to study the change of coal and rock correlation dimension numerical under the different stages of the bursting.(4) Through experiments:Not only the rock acoustic emission sequence is fractal in space, but also times. Correlation dimension increases means an increase in micro-damage, correlation dimension reduction represents localized damage. Along with the load, Fractal dimension value size has changed, From the initial load fluctuations to continue to decline. When the fractal dimension is reduced to the lowest, Coal and rock burst.