Ebrahim Sadeghpour - Mechanical Engineering Department, Amirkabir University of Technology
Mojtaba Sadighi - Mechanical Engineering Department, Amirkabir University of Technology
Abdolreza Ohadi - Mechanical Engineering Department, Amirkabir University of Technology

The extended higher order sandwich panel theory is used to evaluate the free vibration response of a debonded sandwich beam. The main novelty of this paper is the consideration of the longitudinal stress in the core. Although this stress component has a minor effect in fully bonded sandwich beam, however, it becomes important for a debonded beam where the shear stress could not successfully be transferred through the core. It will be shown that neglect of the longitudinal stress could result in an appreciable error in evaluation of the natural frequencies. In addition, the model is improved by introducing the first order shear deformation theory to the facesheet. This matter enhances the accuracy of the approach and is useful for modeling of various boundary conditions in Rayleigh-Ritz method. The results have been validated by ANSYS simulation and provided for different boundary conditions. Also, the effect of debonding length and location has been studied and it was observed that the influence of debonding location on a particular mode is related to the shear stress distribution corresponds to that mode.

Free vibration, EHSAPT, debonded sandwich beam, Rayleigh-Ritz method