Coupled glass and structure response of conventional curtain walls subjected to blast loads: validation tests and analysis

Abstract

This paper presents comparisons of analysis predictions and shock tube test results from a recent dynamic test program involving a conventional Enclos curtain wall system designed solely for wind and gravity loads. Measured blast wave induced glazing response and mullion deflections are compared to response predictions made using fast running nonlinear finite element analysis (FEA) techniques incorporating LS-DYNA based finite element analysis of structural mullions and FEA implementation of statistical glass fracture prediction techniques. The design-level nonlinear finite element analysis was performed using WhAM [window (hazard) analysis module], a fast-running, web-based design tool for blast-loaded curtain wall systems. WhAM was developed by Protection Engineering Consultants (PEC) with support from the Enclos Advanced Technology Studio. Post-test comparisons between measured and predicted system and component-level response were carried out to (a) evaluate the accuracy of WhAM, and (b) illustrate how the precision test data can be used to enhance certain features of the WhAM software such as its glass material model (an LS-DYNA user-defined constitutive model with probabilistic failure criterion based on the ASTM E1300 glass failure prediction model and dynamic test data) and simplified modeling techniques for connection details. Note that SI units are used throughout the text of this paper. American/imperial units are also provided in tables when raw data was originally recorded in those units. Data plots resulting from raw data are also presented in American/imperial units.