腹板开孔的H型吊杆横风向驰振特性试验研究

Experimental Study of Across-Wind Galloping of H-Shaped Hangers with Web Hole

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.