【作者】 张刚刚；

【导师】 徐岳；

【作者基本信息】 长安大学 ， 桥梁与隧道工程， 2004， 硕士

【摘要】 本文以国内外大量有关结构损伤识别、神经网络资料的收集分析为基础，总结了三类全局损伤识别方法：动力指纹法、模型修正法、神经网络法。系统地论述了各自方法的理论、公式及使用方法，并比较和分析了各自方法的优点与不足。根据桥梁结构损伤识别与神经网络的发展前景，提出了将径向基函数(RBF)神经网络应用于桥梁损伤识别的方法。 根据神经网络在结构损伤识别的已有成果，并对BP神经网络、RBF神经网络、概率神经网络PNN性能进行了分析，提出将RBF神经网络用于桥梁损伤识别研究，给出应用方法步骤。 根据丹山水库斜拉桥设计、施工资料，对该桥进行了有限元建模与动力分析。集中考虑了桥梁结构单构件损伤、两个构件损伤、三个构件损伤三类损伤工况，分别采用了振动频率、振型模态、曲率模态三种指标作为神经网络的输入参数，采集各损伤状态下的样本数据，共建立9个RBF神经网络模型进行了桥梁损伤识别的研究。研究表明RBF神经网络可用于识别桥梁结构损伤位置和损伤程度。更多还原

【Abstract】 On the basis of collection and analysis of the data about structural damage detection, artificial neural networks, three global damage identification methods are summarized, including: signature analysis approaches, model updating approaches, neural networks approaches. The theories, formulations and usages are discussed systematically; the predominance and shortcomings of each method are compared and analyzed. Combined with the prospect of bridge damage detection and artificial neural networks, a bridge damage detection method based on RBF neural networks is presented in this paper.Through analyzing the research findings of structural damage identification based on artificial neural networks and comparing the capabilities of BP, RBF and probabilistic neural networks, this paper presents that bridge damage detection can be researched based on RBF neural networks and the process is given.According to the design and construction data of Dan Shan reservoir cable-stayed bridge, damage-detection-oriented finite element model of the bridge is established and the free vibration analysis is then carried out. The focus of the research is placed on three instances, including: one component of the bridge is damaged; two components and three components are damaged. Modal frequencies, mode shapes, curvature mode are used as RBF neural networks import vector respectively; sample data of each damaged state are collected; 9 RBF neural networks models are established for researching bridge damage detection. The result indicates RBF neural networks can detect not only the damage position but the damage degree.更多还原