- 學位論文
應用紅外線熱顯像儀於結構健康監測
Using Infrared Thermal Imager for Structural Health Monitoring
摘要
本研究利用紅外線熱顯像儀進行結構健康監測，以門型壓克力模型為實驗對象，並利用電熱片做為結構標記點，紀錄結構響應。此外，以加速規進行驗證，發現其平均自然頻率誤差為3.93%，並發現誤差來源可能為空間解析度與採樣頻率的差異。而振型部份以模態置信準則量化其差異，發現MAC值為0.9963，高度一致性。為了確保未來可以將紅外線熱顯像儀應用於結構健康監測，本研究採用低模態即可識別結構破壞的振型曲率法，在第一模態時就成功定位破壞位置。另一方面，為凸顯紅外線熱顯像儀相對於一般光學相機的優勢，設計夜晚、遮蔽物、雲霧環境，證實熱顯像儀可以於視線不佳的環境進行量測。最後，若未來要將此方法應用於大型結構上，勢必會面臨因解析度不足而無法進行全域量測的難題，因此本研究提出分段量測的方法，以振型重組、畸變修正克服此難題，並以三層樓壓克力模型為實驗對象，與加速規比較，其MAC值為0.9810，吻合度極高。
並列摘要
In this study, the infrared thermal imager was used for structural health monitoring. The gate-type acrylic model was used as the experimental object, and the electric heating film was used as the structural marker point to record the structural response. In addition, the acceleration is verified by the acceleration gauge, and the average natural frequency error is found to be 3.93%. It is found that the error source may be the difference between the spatial resolution and the sample rate. The mode shape is quantized by the modal confidence criterion(MAC), and the MAC value is found to be 0.9963 between accerometer and thermal imager, which is highly consistent. In order to ensure that the infrared thermal imager can be applied to structural health monitoring in the future, this model uses a mode shape curvature method (MSCM) that can identify structural damage in a low mode, and successfully locates the damage location in the first mode. On the other hand, in order to highlight the advantages of the infrared thermal imager over the general optical camera, the night, the shelter, and the cloud environment are designed to confirm that the thermal imager can be measured in an environment with poor visibility. Finally, if this method is to be applied to large-scale structures in the future, it will inevitably face the problem of being unable to perform global measurement due to insufficient resolution. Therefore, this study proposes a method of segmentation measurement, which overcomes this by mode reorganization and distortion correction. The problem is that the three-story acrylic model is the experimental object. Compared with the acceleration gauge, the MAC value is 0.9810, and the degree of coincidence is extremely high.