不同水温下花岗岩声发射信号的小波分形盒维数研究

Study on the Wavelet and Fractal Box-counting Dimension of Granite's AE Signals Under Different Water Temperatures

为探讨不同水温下花岗岩劣化过程声发射特征,通过RLW-3000型测试系统和PCI-2型声发射系统,对自然干燥,50℃含水,100℃含水3类条件下花岗岩位移加载下声发射信号的小波分形盒维数进行试验研究。研究表明,加载过程峰值频率的变化规律能很好地反映水温对花岗岩声发射特征的影响,50℃与100℃水温条件下声发射信号的峰值频率高于自然干燥的峰值频率,前两者的峰值频率区别不大;主频范围的分形盒维数能定量反映不同水温下花岗岩声发射信号的差异,可为深入研究不同水温花岗岩声发射信号特征提供依据。

In order to study the AE characteristics of failure process of granite,the tests were carried out to obtain the wavelet and fractal box-counting dimension of AE signals for three granite samples under natural drying,as well as water temperatures of 50℃and 100℃.In the tests,hydraulic-pressure servo testing system RLW-3000 and AE instrument PCI-2were applied.Results showed that peak frequency variation during the loading process could well reflect the effects of water temperatures on AE characteristics of granite.The peak frequencies under the water temperatures of 50℃and100℃,which varied rarely,were higher than that under natural drying.The fractal dimension box of specified frequency bands could reflect the differences of AE signals for granite under different water temperatures.This study results provided a reference for more detailed studies on AE characteristics of granites under different water temperatures.