等值靜力風載重於橋梁設計上的應用

Application of Equivalent Static Wind Loads on Bridge Design

林堉溢(Yuh-Yi Lin) ； 王彬(Ping Wang)

《結構工程》 29卷3期 (2014/09) Pp. 27-39

https://doi.org/10.6849/SE.201409_29(3).0002

摘要

本文目的是利用橋樑抖振理論與風洞實驗所得之氣動力參數，提出一等值靜力風載重表示式，使橋樑設計工程師能以此等值靜力風載重與其他型式載重做組合，以利結構分析及設計使用。等值靜力風載重包含靜、動態風力效應，其中動態效應分別考慮背景及共振部分。本文背景部分分別採用LRC(Loading Response Correlation)法及慣性力分佈型式，並比較兩者之差異，而共振部分則是依慣性力分佈型式。本文以一簡支樑及一斜張橋為例，前者是用來與文獻結果做比對，來驗證此方法之正確性；而後者則是利用兩種方式分別推導其等值靜力風載重，一為利用風力係數、顫振導數及理論頻譜推導，二為利用斷面模型風洞實驗所量測之位移來推導其等值靜力風載重。

關鍵字

等值靜力風載重 ； 橋樑設計 ； 抖振 ； 斷面模型 ； 風洞實驗

並列摘要

In this paper, an approach to generate the equivalent static wind loads at the design wind speed based on buffeting theory and the information obtained from wind tunnel tests is presented. Using this approach, bridge engineers are able to obtain the equivalent static wind loads and then easily to combine these wind loads with other loads for use of structural analysis and design. The equivalent static wind loads include static and dynamic effects. The dynamic effects are generally divided into the background and the resonant components. Two methods to generate the background components are presented in this paper. One is LRC approach and the other is based on the inertia load distribution. The comparison of the results between these two methods is discussed. The resonant components basically follow the inertia load distribution. Two examples, including a simply supported beam and a cable-stayed bridge, are used to examine the validity and applicability of the approach. Two types of equivalent static wind loads are generated in the cable-stayed bridge example. One is derived from buffeting theory utilizing static force coefficients, flutter derivatives and wind force spectrum. The other is formulated based on the responses measured from the section model tests.

並列關鍵字

equivalent static wind loads ； bridge design ； buffeting ； section model ； wind tunnel test