通过节段模型静力三分力与测振风洞试验,研究了0°~90°风偏角下不同宽高比B/H与不同腹板开孔率的H型吊杆横风向驰振特性.B/H=2.4的模型静力试验显示:腹板全封闭时,在0°~8°与64°~90°偏角区间内存在驰振失稳可能,随开孔率增大,驰振失稳偏角区间有所减小且失稳危险性有所降低.B/H=2.4的模型测振试验显示:腹板全封闭模型在0°与5°偏角较低风速即发生了驰振;开孔率为14%与27%的模型试验风速区间内均无驰振现象,不过开孔率为38%模型在80°,85°,90°偏角高于90m/s风速下均发生了驰振.宽高比B/H=1.6腹板全封闭模型试验显示,0°与5°偏角较低风速下也出现了横风向驰振;开孔率38%模型在85°与90°偏角高于110m/s的风速下也发生了驰振.与改变宽高比相比,适度腹板开孔可明显改善H型吊杆驰振特性.
A wind tunnel study of the galloping response of H-shaped slender hangers with different aspect ratios (B/H) and sizes of slotted web was carried out using both static tests and dynamic response tests. Static test results from the models for aspect ratio B/H = 2.4 showed that galloping instability could occur at the yaw angles from 0°-8° and 64°-90° for the H-shaped model without web slot, and the aerodynamic performance was expected to improve through slotting increase, though the stability of galloping was slightly reduced for model with a slot area ratio of 38 %. The results of dynamic response tests further confirmed that, for aspect ratio B/H = 2.4, the galloping instability initiated around a prototype wind velocity of 30 m/s for the model without web hole under the yaw angles of 0° and 5°. Moreover, no galloping was observed under the slot area ratio of 14 % and 27 %. However, galloping was also observed over a wind velocity of 90 m/s for model with a slot area ratio of 38 % under the angles of 80°, 85°and 90°. Additionally, for aspect ratio B/H = 1.6, galloping instability also occurred around a wind velocity of 24 m/s for the model without web slot at the angles of 0° and 5°, and for the model with a slot area ratio of 38 96, galloping occurred around 24 m/s under the angles of 85° and 90°. It has been seen that proper web slot has a significant with the change of the aspect ratio B/H. effect on restraining the galloping instability, compared with the change of the aspect ratio B/H.