Temperature sensitivity assessment of vibration-based damage identification techniques

This paper presents the study on the temperature sensitivity of some vibration-based damage identification techniques. With the help of a simple supported beam with different damage levels, reliability of these techniques for damage identification in a changing environmental temperature condition was investigated. The temperature effect was considered as the change in modulus of elasticity of the material. The techniques evaluated herein are based on measured modal parameters which use only few mode shapes and/or modal frequencies of the structure that can easily be obtained by dynamic tests. The effect of temperature on identification of different level of damages at different locations was evaluated. The studied results show that both damage localization and quantification can be affected in presence of the temperature effect which can lead the damage detection unreliable. Among the studied methods, frequency based damage detection method and change in flexibility method are found to be more sensitive to the temperature effect. Copyright © 2009 Tech Science Press.