橋梁動態荷重識別理論與試驗

Moving Force Identification Theory and Experiment for Beam and Bridge

陳宥廷(Yu-ting Chen)

指導教授 ： 王仲宇

國立中央大學/工學院/土木工程學系/碩士(2011年)

摘要

由於超載的車輛對道路橋梁等設施危害極大，有效的車輛荷重辨識系統是非常重要的。而一般傳統的靜態地磅站受限於地形與交通的影響，因而延伸出動態地磅(Weight in Motion, WIM)的概念。雖然此研究發展至今已有五十年之久，但目前這類產品在荷重的識別上並不精確，導致此類系統僅能初步篩選出可能超載之車輛。本研究採用Law, S. S. 所提出的時間域識別法(TDM)作為基本理論，藉由ANSYS 軟體數值模擬與實驗室試驗，對此理論方法在推導過程中數學模型假設的合理性以及其使用上的限制做逐步探討。另外，對利用撓度與彎矩兩種反應的識別效果做比較。最後，結合橋梁結構各大梁與荷重間存在反應識別分配係數的概念，有效簡化複合結構，順利對二維結構進行荷重的識別。此理論優點在於無須建立軸重識別資料庫以及具有力學理論作為基礎，將會是一套具有實際運用與發展空間的動態識別理論。

關鍵字

反應識別分配係數 ； 荷重識別 ； 動態地磅 ； 時間域識別法

並列摘要

Since overloading vehicles result in great damage to roads and bridges, it is important to have an effective force identification system. In general, the traditional weighbridge station in static state is confined due to the influence of terrain and traffic; therefore, it extends a concept of Weight in Motion (WIM). Although the development
of this research has been fifty years, the moving force identification on products is not accurate. Instead, the system can only initially screen the vehicles which are likely to be overloaded. Hence, this study adopts Time Domain Method (TDM), proposed by Law, S. S., to be the basic theory. Through the numerical simulation and laboratorial testing, this study discusses the rationality of theoretical math model and the restrictions of using. In addition, it c ompares the results of identification between deflection and bending moment reactions. Finally, combine the structures of bridges and the concept of response identification distribution coefficient. By this, it simplifies the complex structures and makes it possible to identify the force of two-dimensional structure. The advantage of this theory is that it doesn’t need to create axle load identification databases; moreover, it is also based on the mechanical theory. Therefore, this theory will become practical and potential in the field of moving force identification.

並列關鍵字

Response Identification Distribution Coefficient ； Moving Force Identification ； Time Domain Method (TDM) ； Weight in Motion (WIM)

參考文獻

[1] Uhl, T., “The Inverse Identification Problem and Its Technical Application,”

[2] O''Connor, C. and Chan, T. H. T., “ Dynamic Wheel Loads from Bridge Strains,”

Structural Engineering American Society of Civil Engineers, Vol. 114,

pp.1703-1723 (1988).

[3] Law, S. S. and Chan, T. H. T., “Moving Force Identification: A Time Domain