評估軌道車輛行駛安全性的背景理論多以Nadal提出之脫軌係數來訂定相關規範，其中輪軌接觸的垂向力與側向力為計算脫軌係數中最為重要的參數之一，輪軌接觸力會隨時間與位置不斷變化，然而隨時間連續的輪軌接觸力量測不易。
本文比較應變規量測法與傳遞路徑分析法的優缺點，選擇以傳遞路徑分析法量測輪軌接觸力，將加速規佈置於模型上，透過衝擊錘試驗與操作振動量測取得系統頻率響應函數與模型運動時的加速度反應，並使用傳遞路徑分析法結合兩實驗之結果評估輪軌接觸力。
為驗證傳遞路徑分析法用於評估軌道車輛輪軌接觸力之可靠度，本文利用Simpack多體動力學軟體模擬實驗模型之輪軌接觸力，比對實驗結果與模擬結果。結果顯示輪軌接觸垂向動態力平均誤差約7.4%，輪軌接觸側向動態力平均誤差約9.2%，初步驗證了傳遞路徑分析法用於量測軌道車輛輪軌接觸力之可行性。期待未來此量測法能搭配不同操作狀態仍至實車上的應用，若長時間監控可做為軌道車輛之安全依據及軌道之養護參考。

The derailment coefficient is a major indicator for evaluating the safety of the rail vehicles, and the vertical force and the lateral force in the Wheel/Rail Contact are one of the most important parameters for calculating the derailment coefficient.
This study compared the strain gauge method and Transfer Path Analysis. We chose to measure the Wheel/Rail Contact Force by the Transfer Path Analysis. We placed the accelerometer on the model, and measured The Frequency Response Function of the system and acceleration response when the model was operating through the impact testing and the operational vibration and used the Transfer Path Analysis to combine the results of the two experiments to evaluate the Wheel/Rail Contact Force.
To verify the reliability of the Transfer Path Analysis used to evaluate the Wheel/Rail Contact Force, this study used SIMPACK to simulate the Wheel/Rail Contact Force of the model. The results showed that the mean error of the vertical force in the wheel/rail contact force was about 7.4%, and the mean error of the lateral force in the wheel/rail contact was about 9.2%, which preliminarily verified the feasibility of the Transfer Path Analysis for measuring the Wheel/Rail Contact Force.

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