中文摘要：

双层桥面桁架梁气动性能复杂，已有研究较为少见。以某双层桥面桁架三塔悬索桥设计方案为背景，通过节段模型风洞试验，研究了栏杆透风率与高度、双层桥面板中央开槽、中央稳定板等多种气动措施对颤振临界风速的影响。结果表明：该桥原始断面在-3°、0°、＋3°三种风攻角下，颤振临界风速均小于颤振检验风速，存在发生颤振失稳的可能性；中央稳定板的高度对颤振临界风速影响较大，上层桥面设置上中央稳定板能提高桥梁的颤振临界风速；上、下双层桥面板均中央开槽能够显著提高0°风攻角下的颤振临界风速，但使正攻角下的颤振临界风速有所降低；采用上、下双层桥面板中央开槽、合理地设置中央稳定板和改变栏杆透风率等气动综合措施，能使该桥在各攻角情况下的颤振临界风速满足要求。

英文摘要：

Aerodynamic characteristics of double-deck truss-stiffened girders are complex, while existing research is relatively scarce. Taking a double-deck truss-stiffened girder three-tower suspension bridge as the research object, influences of aerodynamic measurements, including the ventilation rate, height of the balustrades, central slotting of upper and lower decks and central stabilizer, on the flutter critical wind speed were studied by section model wind tunnel tests. The results show that flutter critical wind speeds of original cross-section are less than the corresponding flutter checking wind speed at wind attack angles of-3°, 0° and ＋3°, leading to the possibilities of flutter. The height of the central stabilizer has prominent effects on the flutter critical speed, and the upper central stabilizer on the upper deck can increase the flutter critical wind speeds. The flutter critical wind speed can be increased greatly at the wind attack angle of 0° when centers of upper and lower decks are slotted, while the speed may decrease at a positive wind attack angle. The combined aerodynamic measurements of central slotting of upper and lower decks, reasonably setting the stabilizer and changing the ventilation rate of balustrades can make the flutter critical wind speeds of the bridge meet the requirements at each wind attack angle.