地面效应对引发了景观桥的振动和连贯模式
Hao Li1, Qingchi Zhu2, Hongfu Zhang3
1CCCC Second Harbor Engineering Company LTD, Wuhan, 430040, China.
Scientific reports
|March 24, 2025
概括
在宽桥上,地面效应显著抑制了引发的振动 (VIV). 减少桥与地面之间的距离几乎消除了VIV,当地面效应存在时,风角的影响最小.
科学领域:
- 土木工程 土木工程是指土木工程.
- 空气动力学 航空动力学
- 结构动力学 结构动力学
背景情况:
- 引发的振动 (VIV) 对桥梁结构,特别是宽梁设计构成重大风险.
- 了解空气动力学力及其与结构几何学的相互作用对于沿海环境中的桥梁安全至关重要.
研究的目的:
- 为了研究宽 Π 形主梁桥的 VIV 性能.
- 分析地面效应 (梁底与地面之间的距离) 对VIV的影响.
- 探索风的攻击角度和地面接近对桥梁动态的综合影响.
主要方法:
- 进行了断面模型风洞测试.
- 为了进一步验证,使用了数值模拟.
- 使用高阶动态模式分解 (HODMD) 来分析流场.
主要成果:
- 风的攻击角度显著影响垂直曲VIV.
- 随着梁与地面距离的减少,VIV振幅会降低.
- 地面效应大大抑制了VIV,特别是在近距离.
- 第一个模式 (M1) 主导着地面效应,在自由振动期间的模式能量减少.
结论:
- 接地效应是缓解宽 Π 形桥梁的 VIV 的关键因素.
- 桥梁的设计和放置必须考虑地面的近距离,以确保空气动力学稳定性.
- HODMD有效地识别了影响空气动力学现象的主导模式.
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