The bending strength of flat glass panels including the effects of their edges, is commonly determined by means of the four-point bending test method. This is an established and reliable method. However, when testing glass thinner than 3 mm, large deformation may occur. This means that the calculated stresses might not correspond to the actual, as the hypothesis behind the small deformation theory does no longer hold. Furthermore, it might occur that the specimen slips out of the supports, compelling the testing impossible. An alternative method, suitable for thin glass, consists of inducing an increasing curvature from flat until fracture. The curvature is to be constant along the length of the specimen at any time. The stress at fracture is calculated by knowing the corresponding radius or the applied bending moment. The equipment capable of performing this test is the clamp bender whereby the glass is held by two clamps at the specimen’s ends. Rotational and translational movement combine to uniaxially bend the glass as desired. This paper explores the validity of the clamp bender for testing thin glass by comparing the results generated by three different test setups developed at TU Darmstadt, TU Dresden and AGC. The three individually developed clamp bender setups follow the same principle, but present a few differences in actuation. Using these three clamp bender test setups, identical series of thin glass specimens were tested. The results showed that the glass fracture strength data coming from different setups match quite well one another. This paper discusses the different test setups and compares the obtained glass strength data. It contributes to the development of a universally applicable, simple and reliable test method for thin glass.

We developed the CPR Tutor, a real-time multimodal feedback system for cardiopulmonary resuscitation (CPR) training. The CPR Tutor detects mistakes using recurrent neural networks for real-time time-series classification. From a multimodal data stream consisting of kinematic and electromyographic data, the CPR Tutor system automatically detects the chest compressions, which are then classified and assessed according to five performance indicators. Based on this assessment, the CPR Tutor provides audio feedback to correct the most critical mistakes and improve the CPR performance. To test the validity of the CPR Tutor, we first collected the data corpus from 10 experts used for model training. Hence, to test the impact of the feedback functionality, we ran a user study involving 10 participants. The CPR Tutor pushes forward the current state of the art of real-time multimodal tutors by providing: 1) an architecture design, 2) a methodological approach to design multimodal feedback and 3) a field study on real-time feedback for CPR training.

This chapter on architectural glass focuses on the use of glass in buildings and structures. It covers a wide variety of glass applications ranging from its most frequent use in facade glazing systems to advanced applications of glass as a load-bearing material. The latter is a relatively young field of application and evolved from the early 1990s from simple beam applications to today's all-glass structures. An overview of flat glass products that are frequently applied in architecture is provided in Sect. 52.1. This includes a discussion of the related float glass production process, processing technologies, surface treatments, and glass functionalities such as insulation and fire resistant and switchable glazing. In addition to these flat glass products, which are most commonly applied in architecture, Sect. 52.2 discusses cast glass products. Cast glass products such as glass channels and glass blocks provide a different typology and offer a different architectural expression from flat glass products and are as such frequently used in exterior facades and interior separation walls. The application of glass in common facade systems and as a load-bearing material in structures is discussed in Sect. 52.3. This includes a reflection on the related design methodologies and safety concepts that deal with the brittle and, thus, inherently unsafe failure behavior of glass. Section 52.4 describes different typologies for connecting glass components such as glass facade panels or structural glass beams. This includes a discussion of classical mechanical connections and more recent adhesive bonding technologies that provide new opportunities for glass engineering. Section 52.5 discusses numerical modeling procedures that can be used in the design and engineering of glass in the architectural domain. Finally, an outlook for future developments in architectural glass is provided in Sect. 52.6.

Stress whitening is a common effect in polymers where an increase in brightness or an increased opacity of the material can be observed under mechanical loading. Investigating the stress whitening effect for the transparent structural silicone adhesive (TSSA), this effect occurs in different forms depending on the applied deformation. The intensity and appearance of whitening in TSSA depends decisively on the type of loading, i.e. under isochoric deformation a spot-wise whitening can be observed, whereas under volumetric loading a very dense, cloud-like whitening becomes visible. In order to clarify why the stress whitening effect occurs at all, experimental investigations are carried out on uniaxial cyclic tensile tests and constrained tensile tests. The special feature of the uniaxial cyclic tensile tests is that they are performed in a miniature tensile testing machine, which is positioned under a light microscope. This makes it possible to observe stress whitening during cyclic deformation at a micro-scale. Furthermore, for the observation of whitening during constrained tensile tests, so-called pancake test are investigated and compared with the results of the uniaxial cyclic tensile tests. Since the whitening effect in the pancake test is in clear contrast to the uniaxial tensile tests, differences of both results are presented. Finally, the causes of both forms of whitening are defined and characterized.