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Four‐point bending test for thermally curved glass – part 2: basics for testing methodology After a validated numerical parameter study about the load‐bearing behaviour of cylindrically curved glass resulted in a four‐point bending test in the first part of this article, the second part shows the development of a testing method. The procedure enables the existent method for testing plate glass to also assess curved specimens with a constant bending radius in three span lengths and two specimens width. In the test, the failure stress will solely be derived from the failure load. In doing so, the geometric, non‐linear behaviour of the specimens will be taken into account as well as the inhomogeneous principal stress distribution on the glass surface and the probabilistic brittle material behaviour. This article is already structured on the basis of a standardisation and shows comprehensive results. The introduction of the concept of effective stress is essential in order to analyse the resulting stress distribution along the glass edge and on the glass surface and to generate correction factors for the evaluation. One example illustrates the application on basis of the linear beam theory and the usage of newly‐defined correction factors for curved glass in order to show applicability. The results are currently under review as part of the EN 1288 standard. They are supposed to facilitate the application of thermally curved glass for an organic and translucent architecture in the near future. [ABSTRACT FROM AUTHOR]

Four‐point bending‐test for thermally curved glass – part 1: experimental and numerical investigations Thermally curved glass provides advanced design areas in civil engineering as well as in vehicle construction and other industries. However, there is no standardised method for testing the bending strength of curved glass which takes into account the material behaviour of glass as a brittle construction material. Such a method was developed by an extensive experimental and numerical study and is now presented in a two‐part article. In its first part, this article presents an experimental programme in order to derive a four‐point bending test as an expansion of the existent plate glass test. Out of a widely varied testing range of 363 specimens, one field of application will be decided on in order to find out which geometries can be tested. A numerical model will be validated with the aid of the resulting relation between the test force and the distortion of the glass surface. In particular, the specific requirements will be discussed for a geometric, non‐linear, numerical test model. Based on that, the concept of effective stress and a test concept – which is ready for standardisation – are presented in the second part of this article. [ABSTRACT FROM AUTHOR]