人行橋振動舒適度評估與調諧質量阻尼器減振之實例驗證

The Vibration Serviceability of Footbridge and Tuned Mass Dampers for Vibration Control of Experiment Validation

廖偉汝(Wei-Ru Liao)

指導教授 ： 鍾立來

國立臺灣大學/工學院/土木工程學研究所/碩士(2016年)

https://doi.org/10.6342/NTU201603163

摘要

隨著材料的發展與現今對於建築美學的重視，輕質、大跨距的橋梁逐漸出現，但這類輕便橋結構剛度較低，其低振頻、低阻尼的特性，可能導致橋梁對於人的步行載重有較明顯的振動反應，過量的振動會使橋上行人有不舒適的感受，因此設計者需要認知到振動舒適性的問題存在。
本研究重點為行人引致橋梁振動的舒適度評估與TMD減振分析。基於國外相關研究，參考國外對於人行載重相關理論與研究成果，歸納出完整的舒適度評估流程。並以國內一座實際案例人行橋進行數值分析，評估振動量是否超出所規定之舒適度限值，並透過現場量測比對模擬與實際的差異。
初步評估舒適度後，此案例橋梁確實存在振動問題，並採用TMD作為橋梁的減振方案。本文以單自由度系統加裝線性被動式TMD，分析加裝TMD後之減振效果，並同樣將數值模擬結果與現場量測做比對。研究結果橋梁在安裝TMD後，能有效減小振動反應，滿足舒適度的要求。
目前國內較缺乏以TMD對人行橋的振動舒適度進行控制的相關研究與實際案例，本文整理出振動舒適度評估與設計流程，並進行實際案例分析與驗證，提供工程師在相關作業上一個參考依據。

關鍵字

人行橋 ； 行人致振動 ； 振動舒適度評估 ； 調諧質量阻尼器 ； 實驗驗證

並列摘要

With the development of materials and architectural aesthetics, more and more lightweight and long span bridges began to emerge. These footbridges have low frequency and low-damping characteristics. These may susceptible for human-induced vibrations and the pedestrian may feel uncomfortable to cross. Therefore, the footbridge designer need to recognize the issues of vibration comfort.
The main objective of this thesis is assessment of vibration comfort of footbridges under pedestrian loading and analyze the reduction vibrations of the footbridge with TMD. There are summed up the evaluation process based on the foreign related research and analyze a case of domestic footbridge. Assessing whether or not the vibration comfort acceptable through compared the difference with measurement and simulation.
After preliminary assessment of comfort, the vibration problem exist in this case can be found. This footbridge case adopted TMD to reduce vertical vibration. In this paper, there are analysis of effect of vibration reduction of SDOF system installed passive TMD and compared the measurement. The results show that the footbridge with TMD meets the requirements of comfort.

並列關鍵字

footbridge ； human-induced vibration ； vibration comfort ； tuned mass damper ； experimental validation

參考文獻

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[9] Deutsches Instiut für Normung: DIN-Fachbericht 102, Betonbrücken, 2003.

[14] Eurocode: Basis of Structural Design – CEN, 2002.