Glass facades are known to be fascinating building systems that require specific design strategies, experimental protocols and simulation tools. Especially for seismic-resistant buildings, their mechanical performance should be verified against possible failure mechanisms. For this, both numerically optimized and robust approaches are needed, along with tools to support designers. Fragility curves represent, in this sense, a practical approach for many structural typologies and systems. In this paper, attention is given to the development and assessment of a geometrically simplified and mechanically optimized FE numerical model for the non-linear dynamic analysis of glass curtain walls (GCWs). Its potential and gaps in its calibration and prediction capacity, both at the global and local level, are addressed on the base of earlier experimental and numerical studies. A fragility analysis is then carried out by taking advantage of the cloud analysis method to verify the real capacity of a typical GCW and the performance restrictions that are presently recommended by existing standards for construction. A total of 60 non-linear dynamic analyses are carried out for GCWs under real seismic acceleration to capture the maximum effects and possible failure mechanisms. An analysis of the parametric results is then carried out for several performance indicators of practical interest and various technical documents of the literature. As shown, there is a major effect of global and local mechanisms that optimized numerical models should properly capture. At the same time, according to existing technical documents, there is a clear need for more efficient limit values and performance indicators for the design of safe and optimized seismic-resistant GCWs.
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