Post-fracture response of blast-loaded monolithic glass

Abstract

This paper investigates the transient dynamic loading and response of blast-loaded monolithic glazing. Blast damage to glazing is a complex phenomenon that is dependent on material properties, structural arrangement and proximity to the explosive source. Accurate models of glazing breakage and post-fracture performance can be challenging. Maximum principal stress exceedence at randomly distributed micro-flaws determines the initial fracture time and location. Many utilise simplified single-degree-of-freedom models to characterise break/no-break with limited capability to model fragment trajectories. Two full-scale blast trials conducted at MOD Shoeburyness investigated the monolithic glazing response as a function of panel thickness and blast stand-off. Bespoke instrumentation and high-speed photography captured the panel response, fragment velocity and blast overpressure, enabling a comparative study against computational fluid dynamics (CFD) analyses, conducted with Air3D. Domain and mesh refinement produced reasonably accurate blast flow replication, permitting overpressure solution remaps. Applied glazing loads were thus configured in an applied element method (AEM) model. Triangulated spatial discretisation permitted fragmentation patterns indicative of monolithic glazing. Synthesising CFD and AEM, this paper outlines accurate representations of the experimental results, demonstrating that the transient dynamic glazing response, including the post-fracture performance, can be modelled with this methodology.