浮動式道床軌道系統中最重要的減振抗噪構件，係浮動式道床底下的彈性支承墊，通常採用天然橡膠、合成橡膠或者是金屬彈簧，彈性支承墊材料性質需要具備高使用壽年與高抵抗疲勞老化之特性。
若浮動式道床彈性支承墊採用天然或合成橡膠，於長時間營運下經過列車動態載重反覆加載，會造成橡膠發生疲勞老化之現象，支承墊垂向勁度將會隨之提高，進而影響到浮動式道床之減振效能。
本文將利用有限元素分析軟體Abaqus/CAE，依據桃園機場捷運延伸線浮動式道床軌道設計圖，建立三維浮動式道床有限元素分析模型，由文獻與現地試驗對模型進行驗證，再接著探討橡膠支承墊於不同疲勞老化程度的情況下，對於列車行經浮動式道床後減振效能的影響。
藉由分析模型所得之浮動式道床插入損失頻譜圖與其總體插入損失，可以得知隨著橡膠老化而支承勁度提升後，浮動式道床插入損失曲線有隨之上移的趨勢、總體插入損失也隨之減少，意即隨著橡膠老化支承勁度提升，浮動式道床減振效能也隨著降低，也會造成隧道仰拱面以及隧道土層接觸面之振動量隨之上升，影響環境振動之大小。

The most important component in the floating slab track (FST) system is the elastic bearing system, natural rubber, synthetic rubber or metal springs are usually used, and the material of the elastic bearing needs to have the characteristic of high service life and high resistance to fatigue and aging.
If the elastic bearing of the FST adopt natural or synthetic rubber, it will cause fatigue and aging of the rubber bearing under the repeated load of the dynamic train load during long-term operation. It will cause fatigue and aging of the rubber and the vertical stiffness of the rubber bearing will increase, which will affect the reduction effect of the FST.
In this research, the commercial finite element software Abaqus/CAE will be used to build a three-dimensional finite element model of the FST which is based on the design diagram of the extension line of the Taoyuan Airport MRT. The model will be verified by literature and the on-site hammer test. After verifying the FST model, the influence on reduction effect of the FST will be discussed under different circumstances of fatigue and aging of the rubber bearing when the train model pass through the FST.
By analyzing the insertion loss spectrum and the overall insertion loss of the FST, we see that the insertion loss spectrum curve of the FST has a trend to move upward and the overall insertion loss of the FST decrease as the rubber ages and the bearing stiffness increase. This means that as the rubber ages, the bearing stiffness increase, the reduction effect of the FST decrease, which will cause the vibration amount of the tunnel invert and the outside-surface increase and the environmental vibration will increase, too.

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