悬索桥的损伤识别

讨论了悬索桥加劲梁的累积损伤识别。识别基于比较完好桥的初始指纹与损伤后的指纹。使用了三个基于ＦＲＦ的波形识别指标：ＷＣＣ，ＩＡＴＭ，ＩＳＡＣ与三个基于振型的识别指标：ＩＣＯＭＡＣ，柔度，和曲率模态，作为指纹来识别悬索桥加劲梁的模拟损伤，并比较了他们的识别能力。结果表明：ＩＡＴＭ和ＷＣＣ识别损伤的能力优于ＩＳＡＣ，但都不能定位损伤；柔度和曲率模态识别能力优于ＩＣＯＭＡＣ，并可以定位损伤。本文还发现应变模态具有较好的损伤识别能力。柔度、曲率和应变模态可用于安全监测系统。

Damage detection of suspension bridges

Damage detection of suspension bridges was discussed. The detection is based on comparison of initial signature (FRF, mode shapes and so on) of intact bridges with that of damaged bridges. Three waveform recognition indices based on FRF: the waveform chain code (WCC), the adaptive template methods ( I ATM ) and the signature assurance criterion ( I SAC ), and three mode shape based methods: the coordinate modal assurance criterion ( I COMAC ), the flexibility and the curvature mode shapes are used for damage detection of suspension bridges. Their sensibilities to damage in deck of Tsing Ma suspension bridge are compared. The application of the strain mode shape method to damage detection was discussed. The results show that among the three waveform recognition indexes, I ATM and WCC are more sensitive to damage than I SAC . All of them, however, can not predict damage locations. The results also show that among the three mode shape based methods, the flexibility and the curvature mode shape are more sensitive to damage than I COMAC , and can localize damage. It is demonstrated by experiment and analysis on clamped uniform beams that strain modal shapes are better for damage detection in some aspects.