基于压电阻抗技术的木梁损伤识别研究

利用压电阻抗技术对粘贴有压电陶瓷(PZT)传感器的无损木梁和带孔洞损伤的木梁进行数值模拟和实验研究，并用损伤指数，即均方根偏差(RMSD)来定量评估木梁的阻抗值随损伤程度和损伤位置的变化关系。计算结果表明，利用压电阻抗法能够有效识别木梁的局部损伤，当PZT贴片和损伤位置的间距一定时，RMSD随损伤程度的增大而增大；当损伤程度一定时，RMSD随PZT贴片和损伤位置间距的增大而减小，数值结果与现有实验结果规律一致。相关结论证明了利用压电阻抗技术检测木梁局部损伤的有效性，可为工程实际提供参考。

Damage Detection for Timber Beams Based on Piezoelectric Impedance Technology

The numerical simulation and experimental study on the non destructive and destructive timber beams with piezoelectric ceramic (PZT) sensors are carried out based on the piezoelectric impedance technology, and the damage index, that is the root mean square deviation (RMSD), is used to quantitatively evaluate the relationship between the impedance value of the timber beams as a function of the damage degree and the damage location. The results indicated that the piezoelectric impedance method could efficiently estimate the local damage. The RMSD value increased with the increase of the damage degree when the distance between the PZT transducer and damage location was fixed, while the RMSD decreased with the increase of the distance between the PZT transducer and damage location when the damage degree was fixed. The numerical results are consistent with the existing experimental results. Both of the numerical results and the experimental results indicate that the piezoelectric impedance method can efficiently detect the local damage of the timber beams, which can provide a reference for engineering practice.