Application of Digital Image Correlation Technique for On-Line Structural Health Monitoring Systems(II)

[[abstract]]台灣地理位置特殊，每年除了有強烈地震威脅之外，固定於夏秋之交的颱風也為人民的生命財產造成極大的損害。但是從世界各國經驗可知，若能及時掌握結構物的性能，則大多數的災害都是可以避免的。現今結構健康診斷技術多以結構物的動態反應為診斷依據。早期只採用結構物振動頻率的指標的方式無法確知結構物破壞位置，對補強之幫助不大。因此目前許多方法都要求有振動模態，以便評估可能的破壞位置。所以在實施上需要有足夠的位移反應資訊。數位影像相關係數法為一非接觸式光學量測技術，近年來由於數位相機像素之提昇，及電腦運算速度的快速發展，數位影像相關係數法被廣泛的應用在不同領域。此方法之優點為不會對觀測物體造成擾動，另外是所需之設備成本不會太高。申請人擬將此量測技術應用於結構即時監測上，達到以少許人力物力來達到結構健康診斷之目的。針對此，研究計劃分三個面向，以三年為期進行研討: 第一(九十六)年度為進行中的計畫。研究重點主要在於建立三維空間資訊重建技術以及建立應用數位影像相關法的振模識別技術。第二(九十七)年度研究重點在於建立數位影像相關係數法的動態監測平台，發展長跨橋樑結構之系統識別與康健診斷技術，並以實驗室結構模型驗證即時監測系統之可行性。第三(九十八)年度研究重點在於探討數位影像結構監測系統與保全監視系統結合之可行性，並建立結構震害監測之室外實況與即時遠端監測實測案例。[[abstract]]Taiwan locates at the very special situation in the world. Many strong earthquake attact the island every year. Also, it should face to typhoon. The natural disaster induced very large lose of life and properties. It’s learned from the history the most loss can be avoid, if the state of the structure can be detected. Most of the structural health monitoring techniques use the dynamical response of the structure to assess the condition of the structure. Recently, the researcher found that the displacement response is necessary for finding the location of damage. The measurement of displacement is important for this purpose. Digital-image-correlation technique is a non- contact-type optical measurement technique. The progress of digital camera and the fast development of the computer calculation velocity cause the digital-image-correlation technique widely applied to different research fields. Advantage of this method is, that the observed object will not be disturbed and the cost of necessary equipment is not too high. The applicant plans to apply this measurement technique to the on line monitoring of structures. The study is divided in three orientations and it will be proceed in three years. The focal point in the first year is to develop the method for reconstruction of 3-dimensional space information, and to develop the modal analysis technique by digital image correlation method. In the second year, a prototype of on line dynamical monitoring system will be conducted. A damage index for long-span bridges will be defined and verified by experimental method in the lab. The Focal point in the third year lies in combination of the security camera system and the structural monitoring system. All of the sub-projects will be combined to set up an integrated Earthquake Rapid-reporting and Decision Support System.[[note]]NSC97-2625-M260-00