本研究旨在發展一套能模擬車軌橋互制動力行為的程式，藉此程式可以分析車輛系統、軌道系統、橋梁系統的動力反應。本研究一共建立了六種車輛模型，由簡單到複雜，鋼軌以及橋梁則都是用向量式有限元(Vector Form Intrinsic Finite Element，VFIFE, V-5)中的三維剛架元元素模擬，因此本程式可在三維空間建立模型。並利用合理之等效勁度模擬有碴軌道，除此之外更考慮了輪軌介面不平順的效應進去。本研究將車軌橋系統分成三大部分討論，第一個部分為車輛系統，第二個部分為軌道系統，第三部份為橋梁系統，三大部分中的鋼軌以及橋梁系統皆利用向量式有限元計算，而軌道系統中包含扣件以及基礎等本研究皆會利用彈簧阻尼模擬之，而上部的車輛系統則藉由矩陣計算，由於三大系統為獨立求解，因此計算簡單，並且藉由與文獻比對，證實本程式能有效模擬車軌橋互制的動力反應，由車橋互制中的移動荷載移動車輛，到車軌互制的移動荷載移動車輛，到最後的車軌橋互制，由數值算例分析結果顯示，本車軌橋互制程式能有效模擬車軌橋互制之非線性動力行為，而且方法相當簡單不需任何龐大矩陣求解與迭代方法。 This research develops a two-dimensional computation code to investigate the vehicle-track-bridge interaction behaviors. The Vector Form Intrinsic Finite Element (VFIFE) method that is capable to do the nonlinear, large deformation and dynamic analysis of solids and structures is adopted to model the behaviors of the railway structure. The particle dynamics algorithm within the VFIFE method does not require solving any vehicle-track interaction matrix. Hence, it is capable to versatile of nonlinear dynamic problems like the motion behaviors of carriages derailment due to the large deformation or failure of the train and the vehicle-track-bridge system under extreme wind, fluid and earthquake excitations. This research divided the analysis of vehicle-track-bridge system into three parts, firstly is the modeling of the six types of vehicle systems, secondly is the theorems and modeling of the rail and bridge system, and thirdly is the algorithms of vehicle-track- bridge interaction analysis. In the proposed analysis method, the responses of train, rail and bridge systems are solved independently at each time step. The interaction among these three systems is tacking into account by using some outputs in the previous time step as the inputs of the current time step. Small time step size is required to pay for this simplification of interaction analysis. Numerical examples demonstrate that the analysis method proposed in this study can effectively and accurately analyze the nonlinear, dynamic behaviors of the vehicle-track-bridge system.
