频率平方变化比法和小波变换在压力管道损伤识别中的应用研究

【作者】 陶恒亮；

【导师】 李洪升；

【作者基本信息】 大连理工大学 ， 工程力学， 2001， 硕士

【摘要】 当前结构振动识别方法在航空、航天、机械等领域故障诊断中取得了巨大的成功，同时也引起了工程界的普遍关注，并试图把它引用到土木工程结构的损伤识别中来，以作为传统方法的补充，因此对工程结构进行损伤识别、定位和损伤程度评估成为近年来十分流行的研究课题。本文正是基于以上理论基础和现状，试图把振动识别方法应用到压力管道的损伤识别上来。 管道运输是与铁路、公路、水运、航运并列的五大运输方式之一，但是由于其应用的特殊性，往往存在很大的安全隐患，所以为了防止管道发生破坏，迫切需要对量大面广的压力管道进行安全评估和寿命预测。本文首先通过查阅相应的国内外文献简要概括了振动损伤识别方法的最新进展；然后介绍了一种结构振动识别方法——频率变化平方比法，将其应用到压力管道的损伤识别上，并对一段压力管道进行了有限元模拟计算损伤检测；其次对本文所用到的小波理论进行了简要介绍，并且利用小波变换通过编制相应的程序对同一段压力管道的时域信号进行了损伤检测，结果表明本文方法在工程损伤检测上具有一定的应用价值，令人满意。更多还原

【Abstract】 At present, the damage identification method based on structure vibration was used for trouble diagnosis in aerospace field and mechanical engineering originally, which was focused by civil engineering and introduced to damage identification of civil engineering as a supplement of traditional methods. And so the detection, location and estimation problem of structural damage has been the subject of much current research in recent years. This paper based on the theory of fundament and actuality and attempted the vibration method which of used to damage detection of the stress pipe.Pipe transportation is one of five top transportation mode, but because of it’s particularity of applications, and not seldom exists many a snake in the grass of safety. So in order to hold in the damage of pipe, and required to detect it imminently. Firstly, this paper in brief summarized the updated development of civil and international document through consulted correlative document; secondly put forth a new method----the method of frequency change square ratio; in the next place introduced briefly the theory of wavelet; lastly detected the damage to a pipe used the method of frequency change square ratio and the theory of wavelet, and the result showed the effectiveness of these method in the engineering.更多还原