基于希尔伯特-黄变换的铁路桥梁结构健康监测

桥梁结构健康监测直观检查法具有一定的局限性。新的基于希尔伯特—黄变换(HHT)的非破坏性桥梁结构健康监测方法,依赖于瞬变荷载测试和简便的数据收集,核心是近年来针对非稳态和非线性时间序列分析而新发展起来的HHT,由经验模态分解和Hilbert谱分析构成。该方法对桥梁结构健康性的最终判断依据是基于数据的非线性特征、自由振动和强迫振动的频率对比、桥梁对轻荷载及重荷载的响应。该方法的优点是:无需以前的数据,简便的数据采集,最少程度地干扰交通,以及细微差别的精确定量解释。工程实例的分析结果表明这种新方法应用于铁路桥梁结构健康监测的可行性。

HHT Based Railway Bridge Structural Health Monitoring

The direct inspection method for bridge structural health monitoring has certain limitations.We have developed a new Hilbert-Huang Transform(HHT) based method for nondestructive instrument structure health monitoring.When applied to Railway bridges,this new method depends on a transient test load and simple data collection.The nuclear of the method is the newly developed HHT for nonstationary and nonlinear time series analysis,which consists of the Empirical Mode Decomposition and Hilbert Spectral Analysis.The final decision on the health of the bridge structure is based on the nonlinear characteristic of the data,on the comparison between the free and the forced vibration frequencies,and on the bridge response to light and heavy loads.This method enjoys many advantages: no prior data required,simple data collection,minimum traffic disruption,and precise and nuance quantitative answers.The result of a case study will be presented,which established the feasibility of this new approach of structural health monitoring for railway bridges.