Numerical and experimental investigation of free vibration of multilayer delaminated composite beams and plates

Abstract

The use of vibration-monitoring techniques as non-destructive methods for detection of delaminations in layered composite beam and plate structures is a current field of interest for many researchers. However, an extensive search of published literature shows that information on numerical and especially experimental investigations into the dynamic behaviour of delaminated layered composite beams and plates is limited. For this reason the present authors have developed theoretical models and carried out an extensive experimental investigation to establish changes in the first three bending natural frequencies due to delaminations. The subsequent results of these numerical calculations are consistent with the results of the corresponding experimental investigations.

As the result of this work models of a finite delaminated beam element and delaminated plate element have been developed. The method of modelling delaminations presented in this work enables its easy modification according to specific cases of damage (i.e. multiple delaminations).