本研究使用 Bernal 所提出的損傷定位向量法(Damage Locating Vector Method)，以外力激振之方式配合頻率域分解法(Frequency Domain Decomposition, FDD)進行結構損傷之識別，欲發展出一套外力激發結構振動後，以量測結果為依據之結構損傷識別之技術。DLV 法主要概念為針對系統損傷前後之柔度差異矩陣為基礎的結構損傷偵測技術，識別出於特定荷載下，其應力為零之構件，並將其判斷為破壞狀態。由數值模擬的結果可知，若結構之柔度矩陣與理論解完全相符之情形下，DLV 法無論於一維、二維亦或是三維之模型中，皆可明確地診斷出結構物受損之位置，且由加權應力指標(Weighted Stress Index, WSI)作為構件是否具有損傷之判別，即使結構中受損部位僅具有 10%之損傷，其方法依舊能夠準確偵測，可見 DLV 法具有相當之敏感性。而本文中亦模擬不同外力情形下(敲擊力與地震力)，以各節點的加速度歷時資料進行 FDD 分析，找出結構自然頻率與其對應下之模態，用以代入 DLV 法中，以此進行結構損傷偵測之分析。;In this study, the Damage Locating Vector Method proposed by Bernal is used to identify structure damage. Using external force excitation and Frequency Domain Decomposition (FDD) to develop a set of structure damage identification technology based on the measurement results after the external force stimulating on the structure. The main concept of the DLV method is based on the flexibility matrix difference between systems before and after damage, identifying components with zero stress under a specific load, and judging them as a failure state. From the numerical simulation results, it can be seen that if the flexibility matrix of the structure is completely consistent with the theoretical solution, the DLV method can clearly diagnose the damage of the structure whether in one-dimensional, two-dimensional or three dimensional models. The damaged components can be judged by the Weighted Stress Index (WSI). Even if the damaged part in the structure has only 10% damage, the method can still accurately detect it. So, it can be seen that DLV method has considerable sensitivity. In this paper, different external forces (impact force and earthquake force) are also simulated, and FDD analysis is carried out with the acceleration chronological data of each node to find out the natural frequencies of the structure and their corresponding mode shapes, which can be substituted into the DLV method and do the analysis of structural damage detection.
