摘要
开展花岗岩剪切声发射监测试验,利用横、纵波2种传感器接收花岗岩剪切破坏过程的声发射信号,分析声发射横、纵波信号的变化规律及其异同点,探讨两类信号变化规律差异性的原因。研究结果表明:剪切破坏过程中声发射横、纵波事件率变化趋势不一致,纵波事件率在弹性阶段达到最大值后降低,峰值应力前出现“平静期”,累计计数呈“S”型变化;横波事件率在临近峰值应力时出现最大值,累计计数呈“指数”型变化。剪切破坏过程声发射横、纵波事件能量变化趋势一致,破坏过程能量不断增大,临近峰值应力能率达到最大值,累计能量陡增。声发射横、纵波信号频率演化和分布差异性明显,纵波主频在6个固定的频率,近似呈条带状演化,而横波频率成分复杂,主频条带状演化不明显;纵波主频集中分布在90~110 kHz,而横波主频离散分布在0~500 kHz。由于横、纵传感器类型的差异,对岩石破裂过程不同频率声发射信号响应机制不同,是二者声发射事件数量变化趋势不一致的原因;横、纵波声发射事件能量变化趋势一致,这可能与二者高能量的信号均呈现低频特征有关。研究成果进一步丰富和完善了对岩石破裂过程声发射信号特征认识,有助于深入揭示岩石破裂灾变机制。
Shear acoustic emission monitoring tests of granite were carried out,and S-and P-waves sensors were used to receive acoustic emission signals.The variation rules,and similarities and differences of S-and P-waves signals of acoustic emission are analyzed,and the difference between the two kinds of signals is discussed.The research results show that the variation trend of acoustic emission S-wave and P-wave event rates is inconsistent in the process of shear failure.The P-wave event rate decreases after reaching the maximum value in the elastic stage,there is a“quiet period”before the peak stress,and the cumulative count changes in an“S”shape.The S-wave event rate reaches its maximum value near the peak stress,and the cumulative count changes exponentially.The energy variation trend of S-wave and P-wave is consistent in shear failure process.During the failure process,the energy increases continuously,and the energy rate near the peak stress reaches the maximum value.The cumulative energy increases sharply.The frequency evolution and distribution of acoustic emission S-wave and P-wave signals are obviously different.The main frequency of the P-wave is at six fixed frequencies and approximately evolves in bands.S-wave frequency components are complex and the evolution of main frequency bands is not obvious.The dominant frequency of P-wave is concentrated in the range of 90-110 kHz,while that of S-wave is discrete in the range of 0-500 kHz.Due to the different types of S-wave and P-wave sensors,the response mechanism of different acoustic emission signals with different frequencies of rock failure process is different,which is the reason for the inconsistent variation trend of the number of acoustic emission events between the two sensors.The energy variation trend of S-wave and P-wave acoustic emission events is consistent,which may be related to the low-frequency characteristics of both high-energy signals.The research results further enrich and improve the understanding of acoustic emission signal characteristics of rock fracture process,which is helpful to reveal the mechanism of rock fracture catastrophes.
作者
刘俊岭
李佳其
梁鹏
李壮
LIU Junling;LI Jiaqi;LIANG Peng;LI Zhuang(School of Mining Engineering,North China University of Science and Technology,Tangshan,Hebei 063210,China;Yisheng Innovation Education Base,North China University of Science and Technology,Tangshan,Hebei 063210,China;Mine Green Intelligent Mining Technology Innovation Center of Hebei Province,Tangshan,Hebei 063210,China)
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2023年第2期429-440,共12页
Chinese Journal of Rock Mechanics and Engineering
基金
国家自然科学基金资助项目(51904105)
河北省自然科学基金资助项目(E2021209052)
国家级大学生创新创业训练计划项目(X2021040)。
关键词
岩石力学
剪切破坏
声发射
横波
纵波
时频特征
rock mechanics
shear failure
acoustic emission
S-wave
P-wave
time frequency characteristics
