在地震负荷下使用适应性递归子空间方法对混凝土大的模态参数递归估计
Xinyi Zhu1, Jianchun Qiu1,2, Yanxin Xu3,4,5
1College of Hydraulic Science and Engineering, Yangzhou University, Yangzhou 225009, China.
Sensors (Basel, Switzerland)
|June 27, 2024
概括
一种自适应递归子空间 (ARS) 方法准确地估计了混凝土形大中的模态参数. 这种方法追踪频率和阻尼比率的变化,这对于评估地震损伤和确保结构安全至关重要.
科学领域:
- 结构工程 结构工程
- 地震分析 - - 地震分析
- 振动监测 振动监测 振动监测
背景情况:
- 混凝土门大易受地震破坏,从而改变其动态特性.
- 准确的模式参数识别对于监测结构健康和检测损坏至关重要.
- 现有的方法可能无法完全捕捉受损结构中模式参数的时间变化的性质.
研究的目的:
- 开发和验证一种适应性递归子空间 (ARS) 方法,用于混凝土大中模态参数估计.
- 为了研究在地震负荷下模式参数的演变.
- 为了将已识别的模式参数变化与模拟的损伤进展相关联.
主要方法:
- 提出了一种具有可变遗忘因子的自适应递归子空间 (ARS) 方法,用于递归模态参数估计.
- 使用ABAQUS软件进行地震负荷下混凝土梁大的数值模拟,采用混凝土损坏可塑性 (CDP) 模型.
- 实施了ARS方法,使用数值模拟的动态响应来确定模式参数.
主要成果:
- 该ARS方法成功估计了模式参数,揭示了四种初始模式频率的下降趋势.
- 观察到这些模式的缓冲比率同时增加,表明结构退化.
- 在确定的模式参数变化和模拟的损害进展之间显示出强烈的相关性.
结论:
- 拟议的ARS方法对于混凝土门大的递归模态参数估计是有效的.
- 该研究强调了监测模式参数演变对于评估地震损害的重要性.
- 研究结果为了解混凝土门大的动态行为和运行状态提供了宝贵的见解.
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