Impact Resistance of Annealed Glass Panels

Abstract

Annealed glass is by far the most commonly used glazing material in building construction. The resistant properties of glazing panels to wind loading has been studied for a long time based on quasistatic modeling. More recently, the vulnerability of infrastructure and its protection against acts of terrorism has been receiving a great deal of attention, as pioneered by the work of Wu and Hao from within Australia, whereas vulnerability studies by Stewart were specific to glass façades in terrorism scenarios. Emphasis has been on modeling the blast induced pressure and impulses, as they are applied to the panels while the resistant properties of the glazing materials have been based on assumptions used currently in design. Research undertaken by the writers over the past two to three years have revealed scopes of possible improvements to the current models that have been used in defining the resistant properties of glazing materials. Models based on the well known Weibull distribution, although widely assumed in practice, have been found to be not fully consistent with evidence produced experimentally or by analytical simulations. The interaction of the principal stresses surrounding the crack tip and higher mode effects have also been found to have significant effects on the ultimate behavior of the panel. The accurate modeling of these phenomena is particularly important for large panels. This paper provides an update of the redevelopment of a realistic behavioral model for annealed glazing panels subject to impact action. A new simulation procedure that takes various described phenomena into account is presented in this paper.