Zhou Jing, Zhou Zilong, Zhao Yuan, Cai Xin
School of Resources and Safety Engineering, Central South University, Changsha 410083, China.
Sensors (Basel). 2021 Nov 9;21(22):7429. doi: 10.3390/s21227429.
Measuring accurate wave velocity change is a crucial step in damage assessment of building materials such as rock and concrete. The anisotropy caused by the generation of cracks in the damage process and the uncertainty of the damage level of these building materials make it difficult to obtain accurate wave velocity change. We propose a new method to measure the wave velocity change of anisotropic media at any damage level by full-waveform correlation. In this method, the anisotropy caused by the generation of cracks in the damage process is considered. The accuracy of the improved method is verified by numerical simulation and compared with the existing methods. Finally, the proposed method is applied to measure the wave velocity change in the damage process of rock under uniaxial compression. We monitor the failure process of rock by acoustic emission (AE) monitoring system. Compared with the AE ringing count, the result of damage evaluation obtained by the proposed method is more accurate than the other two methods in the stage of increasing rock heterogeneity. These results show that the proposed method is feasible in damage assessment of building materials such as rock and concrete.
测量准确的波速变化是评估岩石和混凝土等建筑材料损伤的关键步骤。损伤过程中裂纹产生所导致的各向异性以及这些建筑材料损伤程度的不确定性，使得获取准确的波速变化变得困难。我们提出了一种通过全波形相关性来测量各向异性介质在任何损伤水平下波速变化的新方法。在该方法中，考虑了损伤过程中裂纹产生所导致的各向异性。通过数值模拟验证了改进方法的准确性，并与现有方法进行了比较。最后，将所提出的方法应用于测量岩石单轴压缩损伤过程中的波速变化。我们通过声发射（AE）监测系统监测岩石的破坏过程。与AE振铃计数相比，在所提出的方法得到的损伤评估结果在岩石非均质性增加阶段比其他两种方法更准确。这些结果表明，所提出的方法在岩石和混凝土等建筑材料的损伤评估中是可行的。
