Structural Glass Systems under Fire: Overview of Design Issues, Experimental Research, and Developments

Abstract

Architectural design concepts incorporating glass beams, panels, or generally load-carrying elements and sti eners for buildings, claddings, windows, and partitions are largely considered in modern high-rise constructions. A multitude of aspects, including motivations related to transparency, aesthetics, illumination, and energy conservation, progressively increased the use and interest for such a still rather innovative constructional material. However, compared to other traditional materials for buildings, standard glass is typically characterized by brittle behaviour and limited tensile resistance. e intrinsic properties of glass, moreover, together with typically limited thickness-to-size ratios for glazing elements, or the mutual interaction of glass components with adjacent constructional elements as a part of full assemblies they belong (i.e., xing systems, sealants, etc.), as well as the combination of mechanical and thermal phenomena, make glass structures highly vulnerable. Special safety design rules are hence required, especially under extreme loading conditions. In this review paper, a state of the art on structural glass systems exposed to re is presented. Careful consideration is paid for actual design methods and general regulations, as well as for existing research outcomes-both at the material and assembly levels-giving evidence of current challenges, issues, and developments.

Basis of Guidelines for Structural Design and Thermal Assessment of Buildings with Hybrid CLT-Glass Elements

“…Accordingly, it must satisfy specific performance limits (EU 2010/31). This is also the case of the CLT-glass facade element herein explored and represents a strategic design step for the assessment/optimization of novel envelopes in general (Zobec et al, 2002;Aldawoud, 2017;Bedon, 2017;Planas et al, 2018).…”

“…Even though several European standards apply to glass products (EN 12543-2; prEN 13474-2), an harmonized and exhaustive Eurocode for the load-bearing design of glass structures in Europe is still in preparation (Feldmann and Di Biase, 2018;CEN/TC 250, 2019a;2019b) and national guidelines for dimensioning or verification of glass elements are available (see for example (CNR-DT 210/2013;Buildings Department, 2018;Feldmann et al, 2014). Further open issues for the design of load-bearing glass elements are represented by elevated thermal exposures and related effects on the mechanical material properties (Bedon, 2017;Bedon and Louter, 2018;Kozlowski et al, 2018;Sjöström et al, 2020).…”

Thermal and Energy-Efficiency Assessment of Novel Hybrid CLT-Glass Facade Elements

“…However, there are still several open questions regarding the design of load-bearing glass. Among others, one of the challenging issues that will be partly addressed in this paper is related to the increased thermal exposure of glass in facades, and its effects on the mechanical properties of load-bearing glass systems [20][21][22][23].…”

Behavior of load‐bearing glass at elevated temperature

“…The effect of temperature and its variation on the structural performance of glass has been a relatively unexplored area for a long time; however, it has gained wider attention in recent years (e.g. Vandebroek [3], Wang et al [4], Louter and Nussbaumer [5], Bedon [6]). Regarding structural applications exposed to elevated temperature and fire, besides the direct influence of temperature on the mechanical and thermal properties of glass, other aspects also play an important role, such as e.g.…”

“…It should be noted that available studies of the material behavior at elevated temperature show some discrepancies and cannot always be directly compared, see e.g. Bedon [6], Li et al [10], Xie et al [11]. The testing of glass strength at elevated temperatures therefore requires further study.…”