Effect of the root crack on natural frequencies of sandwich composite beams

Abstract

This study aims to examine the effect of interface crack on the free vibration response of a sandwich composite beam experimentally and numerically. Natural frequencies in a thin sandwich composite cantilever beam with root crack are determined. The crack with various lengths is opened between the face sheet and foam core, such as 50, 100, 150 and 200 mm. Free vibration tests of these samples are carried out. For the numerical analysis, ANSYS finite element software is used. Results obtained by numerical analyses and experiments are compared and it is seen that there is a good agreement between them.

Keywords

• Sandwich composites, Root crack, Natural frequency, Finite element method.

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