静力破碎花岗岩电磁辐射信号的分形特征

Fractal characteristics of electromagnetic emission signals during granite static crushing

选用球型压头和十字型压头在RMT-150C岩石力学试验机上对花岗岩分别进行不同加载速率的岩石破碎实验,采用KBD5电磁辐射数据采集系统对岩石破碎过程中产生的电磁辐射信号进行采集处理,应用分形理论分析电磁辐射脉冲数的分形特征.实验结果表明:试件在受载过程中电磁辐射脉冲数与时间具有明显的分形特征,并随加载速率增大电磁辐射信号强度增大,分形维数D也增大,具有很好的相关性;在相同速率的岩石加载破碎条件下,十字型压头电磁辐射分形维数D比球型压头的大,与电磁辐射脉冲信号的强度变化呈相同的规律,利用电磁辐射脉冲信号和分形维数D的相同规律可以更全面地反映岩石的真实破裂过程.

On the RMT-150C rock mechanics testing machine, test different loading rates of rock crushing with spherical indenter and cross indenter, using KBD5 electromagnetic emission data acquisition and processing system collect and handle electromagnetic emission signal during rock crushing process. Fractal characteristics of electromagnetic emission pulses were analyzed by fractal theory. The results show, in the process of the specimen loaded, electromagnetic emission pulse number has obvious fractal characteristics with time, and with the increase of the loading rate, the intensity of electromagnetic radiation signal increases, the fractal dimension D also increases which has a good correlation. Under rock loading and crushing of the same rate, cross indenter electromagnetic emission fractal dimension D is larger than spherical indenter , which has the same law to the intensity change of the electromagnetic emission pulse signal, by using the same law of the electromagnetic emission pulse signal and the fractal dimension D, the real fracture process of the rock is more fully reflected.