在公路橋梁中，超載破壞是很重要的一個課題，特別是在交通樞紐亦或是貨運量大的重要公路或橋梁，其破壞程度尤其嚴重，因此建立出橋梁荷載譜是橋梁永續經營必要課題，來檢視橋梁受到重車不斷的循環加載行為時，是如何影響橋梁壽命，藉此推估其壽命及使用年限，將來不論評估強度是需補強或是重建都能夠有個參考的依據，而其中建立荷載譜的第一步就是算出車輛載重，而本文主旨就是為了發展車輛載重識別(Weigh-In-Motion)的方法，透過車輛與橋樑結構之互制行為，來得知車輛載重。 本研究主要是利用商用軟體ANSYS為出發點，目標在於提取ANSYS裡的結構矩陣以及質量矩陣，在由推導出的廣義變形向量與廣義自由度向量之間的關係，以及外力配置矩陣，配合商用軟體的強大建模能力，希望能達成各形式橋梁的反算系統，而在反算理論裡，是以線性離散時間系統(Linear Discrete-Time System)裡面的狀態空間系統(State-Space System)和線性代數中求解近似值的Tikhonov正規化法為基礎，在利用動態規劃(Dynamic Programming)迭代進行反算求解另外引入模態疊加(Modal Superposition)的概念，減少大量計算時間，並將所量測到的應變值進行分析。橋梁結構數值模擬是利用有限元素法來分析，驗證此動態反算理論識別載重之準確度。 ;The main objective for this research is using strain data to develop a Inverse dynamic algorithm in order to calculate the load of moving vehicle。The basis of this algorithm is structure dynamic equation, normally we can easily get inverse answer by inverse matrix, but consider of that there is too many unknowns in the matrix of structure, result that the relationship matrix is ill conditioned, to solve this problem, we introduce a method named Tikhonov regularization which is the most commonly used method of ill-posed problems, and then by using State-Space System to discretize the equation and achieve iterative equation, furthermore, to simplify calculation, we use concept of mode superposition method without losing accuracy and save massive time. We use finite element method to verify algorithm is correct or not, and benchmark the algorithm to see its performance, in the end we use ANSYS to interface our program with stiff matrix and mass matrix.
