Development of a seismic vulnerability evaluation procedure for architectural glass curtain walls

Curtain wall glass is used widely in modern architecture. Analysis and design methods for architectural glass curtain walls subjected to out-of-plane loads due to wind are relatively well-developed, but analogous methods have not been developed for the analysis and design of curtain walls subjected to seismic loads. In this study, by reviewing previous rating systems and performing experimental tests on curtain walls, an analytical methodology is developed to predict the probability of glass breakage in an applied drift for dry-glazed curtain walls with annealed, seamed-edge annealed, heat-strengthened, and fully tempered monolithic architectural glass. The application of a mathematical model is presented to predict seismic vulnerability of typical glass curtain walls. In order to compute the coefficients in this mathematical model, available mock-up test results, strain measurement tests, finite element analyses and statistical simulations are employed. Calibrated finite element models are used to study the general relationship between the applied drift and the corresponding lateral load, as well as the relationship between the generated stress in the glass and the applied drift. The finite element models are also used to study the load-drift relationship of non-typical curtain wall configuration when experimental data are not available. Finally, by the use of mathematical models and statistical simulations, a computer program is developed to compute and draw fragility curves. Fragility curves present the probability of glass breakage in different applied drifts and can be used in the design of new curtain walls or in the evaluation of existing curtain walls. The main objective of this study was to develop an analytical seismic vulnerability evaluation procedure for architectural glass curtain walls. This objective was achieved.