The effective-thickness concept in laminated-glass elements under static loading

Abstract

Laminated glass is a sandwich element consisting of two or more glass sheets, with one or more interlayers of a polymer such as polyvinyl butyral (PVB). The static response of sandwich elements such as laminated-glass beams and plates can be modeled using analytical or numerical models in which the glass is usually modeled as linear-elastic and the PVB as linear-viscoelastic material, respectively. As a way to simplify the laminated-glass calculations, the concept of effective thickness has been recently proposed, which allows the calculation of laminated-glass beams as monolithic beams using an apparent or effective thickness. In this work, equations for the effective thickness of laminated-glass beams are derived from the analytical model proposed by Koutsawa and Daya and the results provided by this model are compared with the models of Bennison et al. and Galuppi and Royer-Carfagni. Finally, some static experimental tests were performed on several laminated-glass beams under distributed loading in order to validate the predictions of the models.