Numerical and experimental study of the peel test for assessment of the glass-PVB interface properties in laminated glass

In an impact event and for post-fracture behaviour, the adhesion between the glass plies and the interlayer is key to achieving the required safety performance and residual load-bearing capacity. Surprisingly, no specific values for the adhesive properties are prescribed by international standards or available in literature. However, direct measurement or calculation is not possible for the existing test methods. In this article, a finite element framework based on the cohesive zone method is developed to characterise the adhesive properties and study the influential factors in a 90° peel test. The resulting values are of similar magnitude as in other publications in the field, but no certainty can be established over them, mainly because large-strain behaviour of PVB interlayer is still not well documented for the observed range of strain rates. Also, it is seen that no direct relation exists between the peel force and Mode I characterisation of the glass/polymer interface, due to plastic deformation of the aluminium backing foil.