摘要
拱桥吊杆、大型桁架的直杆是典型的细长直立杆件,因风致振动而损坏的现象常有发生。直立杆件的风攻角变化范围为0°～360°,远大于水平杆件。因此,大攻角风致振动是细长直立杆件的显著特点。但过去未引起足够注意。风洞试验和理论分析证实H型杆件存在大攻角颤振失稳的现实可能性,直立杆的最低涡激共振风速和驰振临界风速也不一定正好在风沿杆件强轴或弱轴的方向产生,试验研究了H型杆不同高宽比和不同开孔率下共16种截面的抗风性能。腹板适度开孔可提高驰振稳定性,但几乎不能提高扭转颤振稳定性。在上述基础上,提出直立杆件抗风设计的建议。
The hangers of arch bridges and the vertical bars of large truss structures are typical slender vertical members that may be subjected to wind-induced vibration and suffer related damages. The range of the attack angle for the vertical bars is between 0° and 360°,much larger than that for ordinary horizontal structure members. Therefore,wind-induced vibration （VIV） under large attack angles is one of the most special features for slender vertical bars,but the attention has not been adequate. Both wind tunnel test and theoretical analysis manifested the flutter instability of H-shaped members under large attack angles. The most unfavorable performance of VIV and galloping instability may not occur along the weak or strong axis. Wind-resistant wind tunnel tests of a group of 16 H-section members with different height to width ratios and slot ratios were carried. The results indicated that proper design of web holes could increase the stability of galloping,but had no effect on the improvement of torsion flutter instability. Suggestions for wind-resistant design of slender members were provided.
出处
《土木工程学报》
EI
CSCD
北大核心
2010年第2期1-11,共11页
China Civil Engineering Journal
基金
国家自然科学基金重点项目(50738002)
关键词
细长杆件
吊杆
拱桥
风致振动
阻尼
抗风设计
member bars hanger arch bridge wind-induced vibration damping wind-resistant design
