Creating safer and more resilient building facades has become a primary concern in contemporary design, particularly in earthquake-prone regions, where there is a potentially high impact on financial, social and environmental losses. Glazed curtain wall systems are widely used in modern architecture. Yet, despite decades of research efforts aimed at enhancing the understanding of their seismic behaviour, it is not clear how design choices affect the response of glazed facades. This is crucial given the wide range of glass, framing and joint variations that are at our disposal. With a focus on unitized curtain walls, this paper provides insights into the influence of design variables on façade seismic response by means of an extensive experimental campaign and an associated parametric study to test alternative designs under both quasi-static and dynamic loading conditions. The variables considered included variations in unit dimensions, glass and joint aspect ratios, joint and framing detailing, and support conditions. This research delves into a statistical analysis of the experimental results, in order to define parameters such as glass and façade unit rotations, frame elongations and distortions, utilization factors at different intensity levels. The results provide insights that guide façade design decisions for achieving desired seismic performance levels.@en

Occupant satisfaction and acceptance with automated control strategies for dynamic façades is currently a barrier to the upscale of these systems. Building owners, designers and occupants are often unconvinced that an automated control strategy for dynamic façades could really be beneficial for building energy efficiency and occupant satisfaction. Previous work has indicated that an integrated multi-domain approach is required for capturing the influence of façades on occupants. The aim of this paper is to provide new knowledge on whether dynamic automated facades with user override (semi-automated) can outperform manually operated facades in terms of occupant multi-domain satisfaction. Occupant interaction, discomfort, satisfaction and indoor environmental quality were monitored in two different scenarios: one where the façade blinds were automatically controlled, aiming at maximising daylight and outdoor view access whilst mitigating glare, and one in which the façade blinds were manually controlled by the occupants. Results showed that when the façade was controlled by a semi-automated strategy, occupant satisfaction was higher (especially in the thermal environment), despite occupants reported a higher number of discomfort events due to lack of daylight and access to outdoor view. However, to increase occupant acceptance, a better prediction of occupant glare to prevent visual discomfort and maximise daylight and view is necessary.

@en

Unitized curtain walls are glazing facade systems widely used in modern architecture for mid and high rise buildings, due to their benefits in terms of lightness, quality control, ease of construction and quick installation. However, recent earthquake surveys have shown damages to these non-structural elements. Slight-to-moderate damage can cause loss of facade functionality, moderate-to-major damage can provoke severe post-earthquake economic losses and pose a life-threatening danger to both building occupants and pedestrians. Despite recent studies on the seismic behavior of unitized curtain walls, research in this field is still limited and experimental investigations typically neglect the study of the overall facade performance as well as the identification of the full sequence of damage states and the ultimate resistance of the facade components. This paper presents the extensive experimental campaign carried out at the laboratory of Permasteelisa Group, in Vittorio Veneto (Italy), to investigate the seismic behaviour of full-scale unitized curtain walls from a holistic and multi-performance perspective. The research aims at providing information about the serviceability performance and the ultimate limit state of alternative facade designs. The tests involve various facade configurations consisting of dry (gasket) vs. wet (structural silicone) glazing systems with different construction details for glass, frame and joints (dimensions and type). The testing sequence consists of displacement-control dynamic cyclic loading and/or time histories at increasingly seismic intensity levels, accounting for in-plane, out-of-plane and vertical movements. Air infiltration tests, water leakage tests and wind resistance tests are performed before and after the low-intensity seismic tests to study the post-earthquake facade serviceability. This paper discusses the research objectives, the specimen details and the test setup, and provides preliminary experimental results.@en