載重試驗下構件位移與數位影像相關係數法之應用

Digital Image Correlation Method and Deflection Measurements for Structure Members

陳威廷(Wei-Ting Chen)

指導教授 ： 江支弘

朝陽科技大學/理工學院/營建工程系碩士在職專班/碩士(2011年)

摘要

數位影像相關係數法（Digital Image Correlation Method）是一種具有高精度、低成本和即時性的非接觸式量測技術，藉由比對數位影像中局部區域的灰階強度特徵來判斷變形前後的相對位置。本研究成功撰寫出一個以數位影像相關係數法為理論基礎的位移分析軟體，並對戶外的橋梁進行現地量測，希望能瞭解此程式於戶外施做量測的精確度及對橋梁監測的可行性。經過室內實驗的測試，在適當的參數設定下，本研究所開發之DIC位移分析軟體所運算出的結果與經由傳統量測方法（LVDT）所得之位移量差異幾乎都低於3%。藉由和他人撰寫之類似軟體對相同的影像進行分析，也得到相吻合的位移場分佈。程式運算效率上，對單點的位移分析只需要約數秒鐘的時間，而對局部區塊(約100萬畫素)的位移場計算則約可在1個小時內完成。對戶外現地拍攝的影像進行分析，也得到合理的橋梁位移資訊，未來可推廣應用於既有橋梁的位移監測。

關鍵字

數位影像相關係數法 ； 非破壞檢測 ； 位移量測

並列摘要

Digital image correlation methods (DICM) are important tools in experimental solid mechanics. DICM is becoming very versatile and cost effective due to the dramatic improvement over the digital cameras. Current study applies DICM to displacement measurements of full-scale concrete beams. Computer programs are implemented and tested against the contact measurements using a linear variable differential transformer (LVDT). The calculated displacements agree with the LVDT measurements that the difference is mostly within 3%. The DICM programs produce similar displacement fields to those obtained using two computer codes written by other researchers. The DICM programs compute a single-point in merely seconds while completing the displacement calculation for a whole-field region of 100 mega pixels in one hour. Additional tests on the vertical displacement of a highway bridge also achieve a reasonable result which can be extended to health monitoring of bridges.

並列關鍵字

Digital Image Correlation Method ； Nondestructive Testing ； Displacement Measurement

參考文獻

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