DETECTION OF DAMAGE LOCATION IN BEAMS USING DISCRETE WAVELET ANALYSIS

Document Type : Original Article

Authors

1 Professor of structural analysis, Zagazig University, Egypt

2 Professor of steel structures, Cairo University, Egypt

3 Ph.D Student, Structural Eng.Dept.Cairo.

Abstract

Damage detection in structures using vibration analysis has been a subject of
intensive investigation for the last two decades. In this paper, a method for damage
detection using wavelet analysis is presented. MATLAB program is prepared to
simulate a beam, calculate its mode shapes and analyze the first mode shape by
discrete wavelet analysis. The first mode shapes of damaged and undamaged beams
are transformed to the wavelet domain. The difference of the detail coefficients of
damaged and undamaged mode shapes displays accurately the damage location. A
detailed parametric study was conducted by changing the damage location,
intensity as well as the boundary conditions and wavelet families. These studies
have indicated that discrete wavelet transform accurately predicts the damage
location (single or multi damages) from analyzing the first mode shape.