Damage detection of beam by natural frequencies: General theory and procedure

Abstract

Abstract. The frequency equation of single damaged beam has been established for arbitrary boundary conditions that is the main tool for analysis as well as identification of damaged beam by using measured natural frequencies. A procedure for damage detection problem presented in this paper consists of three steps. First, the modelling error is reduced by a model updating procedure, in which the material, geometrical parameters and boundary conditions are updated. Then , measurement data are corrected based on t he updated model. Finally, the damage parameters are identified using updated model and corrected measurement data. Theoretical investigation is illustrated by an example.

Acoustic Emission and Modal Frequency Variation in Concrete Specimens under Four-Point Bending

“…However, the former issue was addressed here only partially (a deeper investigation would have required performing more sophisticated nonlinear analyses), whereas the latter was not addressed at all, it being beyond the scope of the present study. On the other hand, much literature on the evaluation of crack location and depth based on measured natural frequencies (and modes) exists (e.g., see [43][44][45][46][47][48][49][50][51][52]). This work represents a first attempt to correlate AE signals produced by material damage with variations in the natural vibration frequencies of a cracking element.…”