K Torabi - Assistant Professor
M Shariati Nia - PhD Student, Department of Mechanical Engineering, University of Kashan, Kashan, ۸۷۳۱۷۵۱۱۶۷, Iran
M Heidari-Rarani - Assistant Professor, Faculty of Engineering, University of Isfahan, Isfahan, Iran

Detection of delamination in laminated composite structures is great of interest to engineers from the reliability point of view. Vibration-based methods which investigate changes in vibration characteristics (especially natural frequencies) of a structure due to damage are highly promising in this regard. Therefore, a procedure based on the natural frequency is developed in this study to detect the existence of delamination in laminated composite beams and then specify the size and location of delamination.In fact, delaminated composite beams with different size and location of delaminations are modeled in commercial finite element software, ABAQUS, and natural frequencies are extracted from the modal analysis. The numerical results are validated by analytical and experimental results available in the literature. Finally, a database is generated for different sizes and locations of delamination in laminated beams versus natural frequency. An engineer can predict the frequency behavior of a delaminated beam by changing the size and location of delamination.

Composite beams, delamination detection, free vibration, finite element method (FEM)