华南理工大学学报(自然科学版) ›› 2005, Vol. 33 ›› Issue (2): 75-78.

• • 上一篇    下一篇

结构裂缝群的小波方法识别和数值模拟

廖锦翔 袁明武   

  1. 北京大学 力学与工程科学系,北京 100871
  • 收稿日期:2004-02-13 出版日期:2005-02-25 发布日期:2005-02-25
  • 通信作者: 廖锦翔(1974-),男,博士生,主要从事桥梁损伤识别和健康监测方面的研究 E-mail:liaojinxiang@263.net
  • 作者简介:廖锦翔(1974-),男,博士生,主要从事桥梁损伤识别和健康监测方面的研究

Identification of Structural Crack Groups by Means of Wavelet Method and the Numerical Simulation of Crack Groups

Liao Jin-xiang  Yuan Ming-Wu   

  1. Dept.of Mechanics and Engineering Science,Peking Univ.,Beijing 100871,China
  • Received:2004-02-13 Online:2005-02-25 Published:2005-02-25
  • Contact: 廖锦翔(1974-),男,博士生,主要从事桥梁损伤识别和健康监测方面的研究 E-mail:liaojinxiang@263.net
  • About author:廖锦翔(1974-),男,博士生,主要从事桥梁损伤识别和健康监测方面的研究

摘要: 为采用相对简单的方法对桥梁进行损伤识别,从而实现对结构健康状况的监测,基于桥梁裂缝常以裂缝群方式出现这一现象,通过Lipschitz指数与小波消失矩之间的关系,利用小波变换极大值在多尺度上的变化规律来表征信号突变点的性质,从而判定信号有无奇异点并确定其位置.并通过带裂缝简支梁有限元模型的静力模拟,运用前述理论,确定裂缝群的发生及位置.结果表明,较之传统方法,文中方法不仅更为经济方便,而且检测结果更为精确可靠.

关键词: 结构裂缝群, 小波变换, 损伤识别, 数值模拟, Lipsehitz指数

Abstract:

The aim of this research is to identify the damages of bridges by using relatively simple methods and to monitor the health situations of the bridge structures.Th is research is based on the fact that cracks usuallv exist in the form of crack groups. By analyzing the relationship between the Lipschitz exponent and the wavelet vanishing moment,the characteristics of the signal breaking points are expressed. based on the multi.scale change rules of the maximum value of wavelet transform.Thus,a method is proposed to determ ine whether there exist singularitiv points in the signal.and where the singularity points are located.By applying the proposed theory to the static force simulation of the finite element model for simple-supported beams with cracks.the oceurrence and location of the crack groups are then determ ined.Th e results indicate that the proposed method is of greater precision, more facili-ty and lower cost than the conventional method.

Key words: structural crack group, wavelet transform, damage detection, numerical simulation, Lipschitz exponent