基于多重分形理论的冲击地压电磁辐射预测

Prediction of rock burst electromagnetic radiation based on multifractal theory

煤岩破坏产生的电磁辐射信号具有多重分形特征,在正阶距区域,多重分形谱宽度趋于一个稳定值,该值能够表征煤岩的冲击破坏。为了提高电磁辐射预测预报煤矿冲击地压的水平,采用物理实验和多重分形理论相结合的方法,研究了煤样变形破坏过程中多重分形谱宽度与其冲击倾向、释放能量的内在关系,结果显示:当阶距q从2增加到7时,多重分形谱宽度趋于一个稳定值,临近主破裂时,达到最大值;煤样主破裂多重分形谱宽度ΔD_(qc)与其冲击能指数和剩余能量均呈正线性关系,与弹性指数呈正对数关系,在此基础上建立了电磁辐射预测冲击地压的量化分级指标体系。利用上述分级指标体系,成功地对7251工作面的冲击地压进行了准确的预测预报。

The electromagnetic radiation(EMR)signals generated by coal and rock failure have multifractal characteristics,in the positive order region,the width of the multifractal spectrum(ΔD_(qc))tends to a stable value,which can represent the impact failure of coal and rock.In order to improve the prediction level of rock burst by EMR,by combining physical experiments with fractal theory,internal relations betweenΔD_(qc),and its impact tendency and remaining energy are studied during coal samples deforming and fracturing.The results show thatΔD_(qc)approaches a stable value with order form q increase from 2 to 7,and reaches the maximum at main rupture of samples;ΔD_(qc)has positive linear relationships with its impact energy index and remaining energy,and has logarithm relationship with its elasticity index.According to above study,quantitative classification index system of preventing rock burst by EMR is built.Using the above classification index system,the rock burst has been predicted accurately and successfully in 7251 working face.