Dynamics and failure analysis of architectural glazing subjected to blast loading

Terrorist bomb attacks and threats are on the rise all over the world. High-explosive detonations cause extensive damage to both the target structure and nearby buildings. It is estimated that the majority of nonfatal injuries from bomb blasts result from flying fragments from architectural glazing. Use of laminated glass, two soda lime glass plies are adhered to a polyvinyl butyral (PVB) interlayer, has the potential for limiting such hazards. Most of the work on laminated glazing subjected to blast loading has been experimental and primarily geared towards product evaluation and certification rather than to understand the failure modes and post-failure response of panels. The stress characteristics and the failure modes of such laminates need to be analyzed and understood.; A three-dimensional nonlinear dynamic finite element model is used to study the dynamic response of a glazing subjected a bomb explosion on ground. For computational efficiency, a closed-form formulation is presented for the blast loading parameters. The glass and PVB are treated as elastic and viscoelastic, respectively. The dynamic response of the glazing is studied using closed-form solutions based on the classical small deflection and the von Karman's thin plate theory. Two-parameter Weibull distribution is adopted to describe the cumulative probability of failure. Effect of various parameters on the damage probability is studied. The size of glass shard (fragment) is determined using the Griffith's energy balance approach.