Characterization of the fatigue behaviour of fibre-reinforced plastics through accelerated fatigue tests of composite beams and plates with electromagnetic shakers

In recent years, the interest for fatigue testing of fibre-reinforced plastics has strongly increased, because composite materials are used more and more in structural load-carrying components. In such components, fatigue life time is much more an issue than in secondary, non-critical components. On the other hand, lab-scale fatigue tests show a lot of limitations and it takes a very long time to characterize the fatigue behaviour of one single type of compotiste material. In this project the use of electrodynamic shakers is considered for resonance fatigue testing of composite beams and plates. The composite coupons are excited at their resonance frequencies and are deliberately kept vibrating at these frequencies. That means that the deformations are very large and that little excitation energy is needed. Also compared to normal testing frequencies of 1-10 Hz with servo-hydraulic machines, the testing frequency is much higher. Preliminary experiments during the last year proved the feasibility of this approach.