Glass in buildings

Cold bent glass is a promising and cost-efficient method for realizing doubly curved glass façades. They are produced by attaching planar glass sheets to curved frames and must keep the occurring stress within safe limits. However, it is very challenging to navigate the design space of cold bent glass panels because of the fragility of the material, which impedes the form finding for practically feasible and aesthetically pleasing cold bent glass façades. We propose an interactive, data-driven approach for designing cold bent glass façades that can be seamlessly integrated into a typical architectural design pipeline. Our method allows non-expert users to interactively edit a parametric surface while providing real-time feedback on the deformed shape and maximum stress of cold bent glass panels. The designs are automatically refined to minimize several fairness criteria, while maximal stresses are kept within glass limits. We achieve interactive frame rates by using a differentiable...

Color Depth is a material-based research project investigating the optical and structural properties of thick glass. The research is driven by an interest in optical gradients of transparency and color, which are designed through a manipulation of geometric form and composition. These qualities can be attributed to the interrelated optical effects created through reflection, refraction, and volume color, in direct correlation to the geometry of individual glass pieces and overall glass assemblies. An example of this can be seen in viewing a monolithic volume of glass that would appear to change color by varying the depths of its form. This concept was originally discussed in Josef Albers’ Interaction of Colour, and applied more specifically to glass in recent essays by Heike Brachlow.  Color Depth utilizes this phenomenon of perceived color variation to construct and analyze architectural glass forms in both physical prototypes and design speculation. To evaluate architectural desig...

This paper examines various ways of combining paper and glass as a laminate and the effects on transparency. Laminate in this context means a layer of paper sandwiched in between layers of glass held together with an adhesive. Different kinds of papers and adhesives were used to study the potentials of glass-paper-laminates as related to transparency and translucency. These laminates may find applications in building construction, safety glass, printed electronics and more. Utilizing a variety of adhesives and papers, qualitative evidence found that epoxy achieves the best with regards to transparency and adheres most effectively.

In the past few decades, the use of glass in buildings has remarkably increased. As a result, several transparent buildings have been constructed, in which the materials have almost disappeared. Given that the advancement of architecture is inextricably linked to the acquisition of general knowledge on future developments, this study was conducted to predict the paths of development that glass structures are likely to take in the future. Investigations such as this increase the possibility of advancing both design and construction at the same speed as technology. To achieve this goal, this study evaluates the present situation by investigating new possibilities and assessing their effect on the development of glass buildings. The findings of this study show that the durability, safety, appearance, and efficiency of transparent buildings can be improved through continuous refinement of designs, replacement of aged elements, prompt repair of damaged protective coatings, and greater exploitation of double-sided screens.

Structural integrity of elements depends on their geometry, function and connections used between them. In this paper new hybrid glass to steel elements are investigated concerning their mechanical behavior and function which directly influences their design and vice versa. Their basic design is tested experimentally and then a flexible design approach including parametrical study is proposed for developing unique structural elements for different application. The concept design takes advantage of the mechanical properties of tempered glass, steel and polymer adhesive and achieves structural geometry which results in high mechanical, structural and architectural potential.

A reinforced glass folded structure has been developed using an innovative connection method. The concept relies on extending the reinforcement outwards from the laminated glass and using it to transfer a significant part of the load. The goal is to accomplish a glass element with high stiffness, connected by using a discrete almost invisible and easily assembled/disassembled mechanism. This paper addresses the main issues regarding the design and fabrication of a 90 • folded structure, the experimental investigation of the out-of-plane compressive response and the construction of a full-scale prototype (2,95 m high and 5,5 m long) at the campus of the University of Minho. It is demonstrated that the system offers both structural and aesthetical advantages. It combines a specific aesthetic, deriving from its hybrid character, with a considerable amount of out-of-plane compressive strength before and after failure.

The mechanism of fracture in glass has been studied extensively. Through it's brittle nature it is an ideal model material. This suitability as a model material unfortunately also makes it a poor engineering material. The unique characteristics of transparency and chemical durability of glass forces the large scale use of this material in architecture and many other engineering branches. The limitations of glass as an engineering material however are a problem creating a requirement for a transparent material with mechanical properties comparable to metals. Research into novel laminated glass based composites has resulted in a concept material that combines the transparency of glass with the structural safety of metals. This material is based on the concept of controlling the crack behaviour of the glass and arresting the cracks using crack bridging by the polymer interlayer in the crack wake.

The materials science sector of the faculty of architecture of Delft University of Technology has for several years been working on the development of novel scientific principles for architectural components that combine trans-parency with the ability to carry loads safely. This is the ZAPPI research programme. Initial research focussed on the development of beams and plates. To complete the basic family of structural components a column was needed. A process to manufacture prototypes of a laminated tubular glass column has been developed. This column is transparent but has a strength and failure behaviour comparable to a steel column of similar dimensions.

Noise protection walls along new high speed railway lines are becoming more and more important for reasons of noise protection. Due to train-induced aerodynamic loads these constructions are repeatedly and heavily loaded and therefore subjected to fatigue problems. For reasons of enhanced aesthetics, and better acceptance of affected population, there is currently an increasing demand for walls with transparent elements, using laminated glass panes. The introduction of laminated glass leads to new aspects to be investigated. The knowledge about the fatigue resistance of laminated glass panes against repeated bending load is very limited. In this paper we present new experimental results of high-cycle fatigue tests (>5x10 6 cycles) of midscale laminated glass beams at different temperature stages. Additionally to the results of the fatigue resistance, we also present our experimental findings on dynamic stiffness for different interlayer materials at different termperatures.

In the last decades, the use of glass in construction has been increased unbelievably as if material has been vanished from transparent buildings. Since the advancement in architecture requires knowledge about the path of future developments, this study was conducted in order to discern the potential of improvements to glass structures as a result of scientific and technological advances. In this way, it increases the chance to move forward in both fields of design and construction at the same speed as technology does. In order to achieve this aim, the study investigated the potential for removing the problems with design and construction of transparent buildings. By this method, it indicated that new possibilities for design optimization and reduction in both probability and risk of damage make it possible to build more beautiful, safer, and more durable glass structures.

Continuously curved, highly transparent free-form facades or roofs are increasingly demanded in architecture. Full glass shells assembled from curved glass elements are a possible answer to meet the exigencies of such transparent envelopes. As glass element dimensions are limited by manufacturing, structural joining is necessary for realising large shells. Hence, feasibility studies undertaken at the ITKE focus on the interaction of structure, geometry, glass elements and joining of full glass shells. The joints are influenced by structural considerations as well as the availability, possible size and curvature of single or double curved glass elements, which can be produced either by cold lamination bending or by heat bending. A comparison of different bent glass types with respect to size, curvature, internal stress states and applicability in glass shells is presented in this paper.

Continuously curved, full glass shells have a large potential for application in freeform façades or roofs. Glass elements needed for such a construction can be fabricated either by heat bending or cold lamination bending. But as the curvature and size of glass laminates are limited by manufacturing restrictions, structural joining is necessary for assembling large shells. Unfortunately, such joint discontinuities conflict with the desired membrane state of the shell. The joint pattern layout has a large influence on the load bearing behaviour, stability and appearance of glass shells. Hence, computational procedures have been used to optimise the joint geometry layout by targeting either at minimising particular joint forces or by following the principal membrane force trajectories of the shell.

As cold bent glass with shape stabilisation through lamination is increasingly used in research and building applications, monitoring solutions for the short-and long term behaviour of such curved glass compounds are necessary. For determining the glass surface stress inside the laminate, a new method applying fibre optical sensors with Bragg gratings has been developed and tested at the ITKE. This type of sensing is based on characteristic, reflected spectra of laser light passing through a waveguide. For determining the parameters influencing the behaviour of cold bent glass laminates, testing series involving different interlayer materials and adhesives for the fibres are conducted. The interior stress is calculated from the Bragg sensors and compared to corresponding FE-models. It is shown that the thin, barely visible fibre optical sensors withstand the laminate manufacturing conditions. In addition, the role of the fibre bond is examined and discussed.

When the visual presence of materials decreases, the maximal transparency creates astounding beauty. In order to enhance transparency, clearer and lighter structures should be used. Although glass is extremely noteworthy as a transparent load bearing material, the structural use of glass is still unfamiliar to architects. Since the advancement in architecture requires knowledge about the path of developments, this study was conducted in order to discern the potential of improvement in glass structures as a result of scientific and technological advances. Through analysis of existing challenges and opportunities, this study aims to investigate the possibility of constructing completely transparent buildings in the near future. The findings indicate that improvements in the field of materials, selection of appropriate forms, the advent of innovative techniques, plus fine-tuning the existing technologies can improve structural efficiency, safety, durability, and transparency of glass buildings, so that the imagination of modern architecture can be realized.

In the past few decades, the use of glass in buildings has remarkably increased. As a result, several transparent buildings have been constructed, in which the materials have almost disappeared. Given that the advancement of architecture is inextricably linked to the acquisition of general knowledge on future developments, this study was conducted to predict the paths of development that glass structures are likely to take in the future. Investigations such as this increase the possibility of advancing both design and construction at the same speed as technology. To achieve this goal, this study evaluates the present situation by investigating new possibilities and assessing their effect on the development of glass buildings. The findings of this study show that the durability, safety, appearance, and efficiency of transparent buildings can be improved through continuous refinement of designs, replacement of aged elements, prompt repair of damaged protective coatings, and greater exploitation of double-sided screens.