Vol. 2, No. 3, 2007

Download this article
Download this article For screen
For printing
Recent Issues

Volume 12
Issue 3, 249–351
Issue 2, 147–247
Issue 1, 1–146

Volume 11, 5 issues

Volume 10, 5 issues

Volume 9, 5 issues

Volume 8, 8 issues

Volume 7, 10 issues

Volume 6, 9 issues

Volume 5, 6 issues

Volume 4, 10 issues

Volume 3, 10 issues

Volume 2, 10 issues

Volume 1, 8 issues

The Journal
Subscriptions
Editorial Board
Research Statement
Scientific Advantage
Submission Guidelines
Submission Form
Author Index
To Appear
 
ISSN: 1559-3959
A proposed method for fatigue crack detection and monitoring using the breathing crack phenomenon and wavelet analysis

Viet Khoa Nguyen and Oluremi A. Olatunbosun

Vol. 2 (2007), No. 3, 399–420
Abstract

In this paper the dynamic behavior of a fatigue cracked beam is investigated. The purpose is to reveal the nonlinear behavior of the structure with fatigue damage by using wavelet transform. A cracked cantilever beam is modeled by the finite element (FE) method using ALGORTM software. A breathing crack is described in the FE method as a surface to surface contact of the two edges of the crack during vibration. Strain time history in the area adjacent to the crack has been analyzed using data processing techniques. Nonlinear effects in signals are usually difficult to detect by conventional data processing methods such as fast Fourier transform. However wavelet transform has recently been shown to be an effective method of detecting such nonlinear effects in signals. Modulus maxima, an important property of wavelet transform, have been used as an indicator of the crack size. Numerical results obtained from the FE analysis are presented in this paper, as well as some experimental results. It is shown that detection of fatigue cracks using breathing behavior and wavelet transform can be used to develop a vibration-based crack detection technique.

Keywords
crack detection, crack monitoring, fatigue crack, breathing crack, closing crack, wavelet transform, wavelet analysis
Milestones
Received: 20 June 2006
Accepted: 23 September 2006
Published: 1 May 2007
Authors
Viet Khoa Nguyen
School of Mechanical Engineering
The University of Birmingham
Edgbaston, Birmingham B15 2TT
United Kingdom
Oluremi A. Olatunbosun
School of Mechanical Engineering
The University of Birmingham
Edgbaston, Birmingham B15 2TT
United Kingdom