NONDESTRUCTIVE EVALUATION OF COMPOSITES IN INFRASTRUCTURE APPLICATIONS

A new and innovative use of composites in the infrastructure involves composite reinforced wood. The economic advantage of using high strength fiber reinforcement in the manufacture of glued laminated woods (glulams) is so substantial (net 25-30%) that active commercialization of this development is underway with several structures already in service. Naturally, one would expect the performance characteristics of these materials to depend heavily upon the quality of the associated wood/composite bondlines. In this paper, several nondestructive evaluation techniques are discussed which hold promise for use in (1) determining bondline quality during manufacture and (2) field inspections of composite reinforced wood products. Another promising use of composites is for reinforcing bridge columns to improve their earthquake resistance. It is important that the composites be of a proper quality and that the bondline between the composite and the underlying column remain intact. Preliminary data from thermographic tests involving bridge column overwrap materials will be presented.