Geoffrey E. Clarkson
Cambridge, ON, Canada
Ultrasonic readings taken from glass reinforced plastic can be related to the elastic modulus, and hence the strength of the material. Research results dating back to the 1960’s have shown that stressing fiberglass reinforced plastics (FRP) has resulted in decreasing the modulus of the material – thus reducing its strength. In service, the stresses applied to FRP have the same effect. Two approaches are proposed for monitoring the condition of structural composites – one is to use a baseline developed from specimens of new FRP combined with theoretical work and the other is to use the results of ultrasonic readings taken from the new structure to be monitored and to use this as the baseline. This paper describes both how both approaches can be used.
Presented at CAMX – The Composites and Advanced Materials Expo, October 13-16, 2014.