Failure mechanisms and residual capacity of annealed glass/SGP laminated beams at room temperature

In construction industry, laminated glass is more and more used for transparent load-bearing building components. It is known that the residual load-carrying capacity after glass breakage of glass/PVB (polyvinyl butyral) laminates is relatively poor, mainly due to the limited stiffness and strength of PVB. For that reason, the failure behaviour of laminates composed with a stiffer and stronger interlayer material, called SentryGlase (R) Plus (SGP), was investigated experimentally. Consequently, 1100 mm long test samples composed of two annealed float glass layers and one SGP interlayer were subjected to destructive in-plane four-points bending tests at room temperature. Subsequently, different stages were distinguished during the failure process, corresponding to a different number of broken glass layers. In spite of the relatively good interlayer material properties and in contradiction to what was expected, the observed post-failure safety was poor. However, the failure mechanisms observed were significantly different from those of glass/PVB beams: due to a lack of local delamination near the glass fracture zone, tear of the SGP interlayer occurred without preceding large visual interlayer elongations. (C) 2008 Elsevier Ltd. All rights reserved.