工作状态下梁及桥梁模态与损伤识别的新方法  

A new approach for modal analysis and damage identification of bridges based on ambient excitation

作　　者：李大军[1] 霍达[1] 

机构地区：[1]北京工业大学建筑工程学院,北京100022

出　　处：《世界地震工程》2006年第3期66-69,共4页World Earthquake Engineering

基　　金：北京市自然科学基金重点项目(8031001)

摘　　要：工作状态下桥梁结构的模态参数识别是桥梁损伤识别的重要环节,考虑桥梁检测的实用性,桥梁检测一般应建立在环境激励的基础上,已有的环境激励下模态参数识别的方法对模态频率的识别的精度较高,而对位移模态的识别则误差较大。提出了一种利用移动质量块在不同位置时对桥梁的模态频率进行多次测量,用各次测得的频率值确定位移模态的新方法,使得位移模态识别的精度接近频率识别的精度,建立了该方法的初步模型,推导了频率与位移模态关系的理论公式,并通过数值模拟对该方法的有效性进行了说明。In this paper, a new modal analysis and damage identification method is developed for bridge structures, in which the vibration modal and curvature modal can be obtained by natural frequency, and so local damage is characterized by only the natural frequency measured from the damaged structures. In contrast with most of the existing vibration-based damage identification methods, which require both the natural frequency and other modal parameters measured from the damaged structure. Finally, a computer simulated case is studied on a beam pined at edges to illustrate capability of the modal data and the damage evaluating method.

关 键 词：桥梁 损伤诊断 模态分析 环境激励 

分 类 号：TU435[建筑科学—岩土工程]