過渡段軌道之動態反應

Dynamic Response of Transitional Rail Structure

施光夏(Kuang-Hsia Shih)

指導教授 ： 洪振發

國立臺灣大學/工學院/工程科學及海洋工程學研究所/碩士(2004年)

https://doi.org/10.6342/NTU.2004.02353

摘要

非道碴式軌道目前在國內部分橋樑、隧道以及新興的軌道系統已開始採用，尤其是新建的捷運與高鐵均採用無碴軌道，也逐漸累積可用研究成果。但是當列車行經混凝土路面或高架橋與土路基交界，或有碴到無碴軌道交界等兩種軌道系統交接處，由於介面不同可能引起額外的衝擊之動態反應，本文重點在探討過渡段此介面的動態反應。由於結構不同介面所引起額外的衝擊之動態反應方面的相關研究不多見，因此，本文即對此一過渡段軌道系統之動態反應進行分析與探討，以期能提升未來台灣在過渡段軌道特性的掌控能力。本文所探討的過渡段軌道的動態特性，內容大致分為兩個部份：
一、對於非道碴式軌道系統（直結式軌道系統）與道碴式軌道系統交接處中設置不同勁度之彈性襯墊，以及不同大地支承交接處，藉由LS-DYNA來計算鋼軌、軌床的動態反應，並比較在20米過渡段軌床後無設置10米軌床之軌道系統之反應。
二、以ANSYS計算出簡化後模型之模態形狀及自然頻率，進一步檢討輪軌共振、軌枕間距、支承勁度與行車速度間之關係。
模型分析方面，本文將軌道模型簡化，以彈性離散支承模擬鋼軌彈性襯墊、軌枕彈性襯墊、道碴支承以及大地支承（包括混凝土及土壤）。

關鍵字

輪軌共振 ； 過渡段軌道 ； 彈性離散支承

並列摘要

When trains pass the connection between concrete part and ground part, viaduct part and ground part, or ballast and non-ballast system, the interface between different structural types may induce higher dynamic response due to the impact of discontinuous stiffness of structure . This paper focus on the dynamic characteristic of the transition rail structures.
The subjects of this paper divides into two parts:
(1) Study on the effects of different stiffness of elastic supports in the connection between ballast and non-ballast railway system to analysis the dynamic response of track and ballast bed. We use LS-DYNA to calculate the response of rail and track structures.
(2) Utilize ANSYS to calculate the mode shape and natural frequency of simplified model, moreover we discuss the rail-wheel resonance, distance of sleeper, stiffness of support and train’s velocity relationship.

並列關鍵字

wheel-track resonance ； transitional rail structure ； elastic discrete support

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