BENDING STIFFNESS OF LAMINATED GLASS ELEMENTS IN STRUCTURAL APPLICATIONS — INFLUENCE OF A ELASTO-VISCOPLASTIC IONOMER INTERLAYER ON THE PRE-BREAKAGE BEHAVIOUR

To investigate the mechanical behaviour of laminated glass with the elasto-viscoplastic ionomer interlayer SentryGlas® by DuPont, an experimental program was executed on full-scale glass laminates. The results of this research improved the insight in the complex mechanical behaviour of this stiff interlayer. More specifically, a clear influence of load duration and temperature could be observed for both creep and relaxation setups during bending experiments. The stiffness reduction due to the load duration and the temperature raise was most significant for the smaller specimens — with a span of 1m — while for the largest specimen — with a span of almost 3 meter — the reduction remained less than 25% of the monolithic bending stiffness, even after a load duration of 48 hours at 65°C.