Determination of elastic constants of glass/epoxy unidirectional laminatesby the vibration testing of plates

Identification of elastic properties of unidirectional glass/epoxy laminate s from the measured eigenfrequencies has been performed. The stiffness of t he laminates has been investigated by a mixed numerical/experimental method employing the vibration test of plates. Elastic constants of laminates hav e been determined by using an identification procedure based on experiment design, the finite-element method and the response-surface approach. Elasti c properties of laminates with two different fibre-surface treatments have been compared. It was found that only for the transverse elastic modulus is there a statistically significant difference between the composites with g ood and poor fibre/matrix adhesion. (C) 1999 Elsevier Science Ltd. All righ ts reserved.