CEN/TS 19100:2021 "Design of glass structures"

This article has been authored by Markus Feldman, Chairman TC 250/SC11, RWTH Aachen University, Institut für Stahlbau und Lehrstuhl für Stahlbau und Leichtmetallbau | Steel Construction Institute

With the new publication of CEN/TS 19100 the design of glass structures is now making its European standardization debut, paving the way for a Eurocode.

Glass has become an increasingly important component of modern architecture, as brightness and transparency are an expression of a modern society being reflected in the built environment. Technical development has progressed so far that glass is no longer just an infill element, but can certainly also be part of the main structure. The used glass building products are now of such quality that glass can be used to achieve sustainability not only in terms of embodied energy, but also in terms of operation. As a result of extensive scientific research, design techniques of verifying mechanical resistance and reliability have been developed to a considerable degree.

However, since the 1st generation of Eurocodes comprised rules for design of the “classical” materials only, it was clear that when setting out the strategic key points for the 2nd generation, European rules for the design of structural glass urgently needed to be provided.

With Mandate M/515 of the European Commission CEN/TC 250 got green light for initiating the process of establishing a corresponding design code. After completion of the preparatory works, CEN/TC 250/SC 11 was commissioned to establish CEN/TS 19100 in three parts, including all relevant aspects of a design code. The aim was to produce a regulatory framework with an overarching concept complementary to the different national standardization needs.

When arranging the contents, the code makers were guided by the requirement that not only simple structures, to be designed separately from the building context, but also integrated components were to be equally standardised in terms of design.

Consequently, complementary to the first part dealing with construction materials and glass specific design principles, a second part was developed for the design of out-of-plane loaded and a third part for the design of in-plane loaded components. The parts of CEN/TS 19100 are by name: “Part 1: Basis of design and materials”, “Part 2: Design of out of plane loaded glass components” and “Part 3: Design of in plane loaded glass components and their mechanical joints”.

Part 1 incorporates the values of basic variables and structural models for glass in construction, thereby enabling a realistic assessment of structural glass performance. It also includes general principles for the assessment of structural glass like requirements for resistance, serviceability, fracture characteristics and glass component failure consequences, where effects inherent to glass and glass specific robustness and redundancy concepts need to be considered, beyond the rules of EN 1990.

Part 2 addresses the design of glass components mainly subjected to out-of-plane loads. It gives a framework for a safe structural analysis including the respective particularities of out-of-plane loaded glasses – covering continuously edge supported as well as point supported components – and moreover offers calculation methods for laminated glasses utilizing an effective thickness approach.

Conclusively, Part 3 covers the design of in-plane-loaded glass components and also focuses on the design of connections and joints of such elements and, obviously, the stability issues arising from the in-plane loading. Like in Part 2 the design of laminated glass considering shear coupling is also dealt with.

Apart from EN 1990 and the material related Eurocodes where relevant, CEN/TS 19100 is used in combination with the actions set out in EN 1991 Eurocode 1 and provides complementary rules and guidance on how to apply the actions when designing structural glass. Moreover, the CEN/TS gives additional rules on glass specific actions, like internal pressures in the cavities of insulating glazing units.

As being a Technical specification document, CEN/TS 19100 does not have the normative status of an EN document. The conversion of CEN/TS 19100 into a new Eurocode part fully compatible with the revised 2nd generation Eurocode suite is an ongoing task within Mandate M/515, and the corresponding EN document is expected to be published by 2025.

The three parts of CEN/TS 19100:2021 “Design of glass structures” are documents prepared by CEN/TC 250/SC 11 Structural Glass to be made available to the CEN Member states by the end of 2021. The documents will be published in English, French or German translations and can be purchased from National Standardization Organizations.

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