温度对桥梁动力特性的影响研究

摘要：环境因素（如温度和行车荷载等）变化会引起的结构动力特性的变异,因此，在基于振动的结构健康监测和损伤识别技术中，如何区分环境因素变化与结构损伤所引起的结构动力特性的变异性，并量化环境因素对结构动力特性的影响显得非常必要。本文在吉昌特大桥通车前对其主桥和引桥的动力响应和温度分别进行了测试。首先，用模态自动识别程序识别得到两座桥的前三阶模态。其次，得出箱梁桥的前三阶模态频率和T型梁桥的第三阶模态频率与温度具有显著的负相关性的结论。最终，分别建立了两座桥的动力特性与温度之间的线性回归模型。

Research on the Influence of Temperature Effects

Abstract: Changes in environmental conditions such as temperature and traffic load affect structural vibration properties. Therefore, it is necessary to discriminate the variation of modal properties due to environmental change from those caused by structural damage, and quantify the environmental effect in vibration-based structural health monitoring and damage identification. Before Ji Chang Bridge was open to traffic, the Dynamic response and the temperature had been test respectively on the main bridge and the approach bridge of it in the paper. Firstly, the first three modes of the two bridge was identified with an automatic modal analysis (AMA) procedure. Secondly, It is found that all the frequencies of the main bridge and only the third modal frequency of the approach bridge have a strong negative correlation with temperature. Finally, Linear regression models between modal properties of the two bridges and temperature are respectively built.