本論文的研究內容主要是以風洞斷面模型實驗來探討切角斷面對橋梁斷面受風反應的影響，並藉模型與原型間的反應轉換關係，將結果轉換到模擬的橋樑上。本研究選用兩種主要的斷面形式，一是深度固定角度改變斷面，另一則是角度固定深度改變斷面。然後改變橋梁斷面的切角比與寬深比，每斷面選用4組不同的切角比與寬深比，共有七支模型進行實驗。 由實驗結果得知，對於角度改變系列而言，角度愈大垂直向抖振反應愈小。就扭轉反應而言，切角比對紊流場中扭轉抖振反應並沒有明確趨勢之影響。對於深度改變系列而言，斷面寬深比愈小，垂直向抖振反應愈小。就扭轉反應而言，寬深比對紊流場中扭轉抖振反應並沒有明確趨勢之影響。此外寬深比愈小的斷面，其在低風速下的渦流振動情形愈明顯，而高風速時，因發生顫振而導致破壞所對應的顫振臨界風速也較低。顫振臨界風速判斷下，無論切角之角度變化或是切角之寬深比變化，其趨勢一為角度越小；另一為寬深比較大的斷面，其相對應之臨界風速較高；反之，一為角度越大；另一為寬深比較小的斷面，其相對應之臨界風速則較低，較不穩定。 This main objective of this thesis is to investigate the effect of triangular edge-fairings on the aerodynamic responses of section models through wind tunnel experiments. The results are then used to predict the aerodynamic responses of the prototype bridge. There are two series of bridge decks in the tests. One is the fixed rectangular section with two triangular edge-fairings on both sides. In this series angles of the fairings are varied. The other is the depths of the rectangular sections are varied with a fixed angle of fairings. There are four section models in each series. The wind tunnel tests include the measurements of the static wind force coefficients and the flutter derivatives in smooth flow and buffeting responses in turbulent flow. For the series of variations of angles of triangular edge-fairings, the experimental results indicate that the vertical buffeting response decreases as the edge angle increases. However, the trend of the torsional responses is not obvious in this series. The flutter wind speed increases as the edge angle decreases. For the series of variations of deck depths, the vertical buffeting response decreases with width-depth ratio. The torsional buffeting response is not sensitive to width-depth ratio. As expected, the flutter wind speed increases with width-depth ratio. The flutter wind speeds respectively obtained from section model test and calculated based on the flutter derivatives are in good agreement.
