Challenging Glass 5

Challenging Glass Conference 5 was held 16 & 17 June 2016 at Ghent University in Belgium.

The conference was organised by Prof. Jan Belis (Ghent University) Dr. Freek Bos (TU Eindhoven) and Dr. Christian Louter (TU Delft).

The conference proceedings have been published by Ghent University.

ISBN 978-90-825-2680-6

Published: 2016-06-16

Front matter

  • CONFERENCE ORGANISERS
    Prof. Jan Belis Ghent University, Ghent, Belgium
    Dr Freek Bos Eindhoven University of Technology, Eindhoven, The Netherlands
    Dr Christian Louter Delft University of Technology, Delft, The Netherlands

    SCIENTIFIC COMMITTEE
    Scientific Committee Chairs
    Prof. Jan Belis Ghent University, Belgium
    Dr Freek Bos Eindhoven University of Technology, The Netherlands
    Dr Christian Louter Delft University of Technology, The Netherlands

    Scientific Committee Members
    Prof. Paulo Cruz University of Minho,...

  • Challenging Glass

    Haim Dotan - Haim Dotain Ltd. (ISR)
    Sven Plieninger - Schlaich Bergermann Partner (DE)
    Agnes Koltay - Koltay Facades (UAE)
    Willem Jan Neutelings - Neutelings Riedijk Architects (NL)
    Gijs Rikken - MVRDV (NL)
    Faidra Oikonomopoulou - TU Delft (NL)

  • Platinum Sponsor: Saint-Gobain

    Gold Sponsors: Dow - Eastman - GlasStress - Kuraray - Sedak - Sika - Tuchschmid

    Silver Sponsor: Eckersley O'Callaghan

  • Related papers are separately and independently published at Glass Structures & Engineering (Springer) and are available at https://link.springer.com/journal/40940/1/1/page/1.

Keynote Contributions

  • The Zhangjiajie Grand Canyon Glass Bridge is the world's tallest and longest pedestrian glass bridge in China and worldwide.

  • The Opus project was designed by Zaha Hadid Architects, for Omniyat in Dubai. It is a 20 story fully glazed building, resembling a cube with the core melted out. The outer flat facades are neutral transparent glazed with silver mirror pattern, while the core area is dark blue 3D formed glazing. To achieve this vision, several glass processing technologies were studied, selected, specified – and some abandoned after further studies. The project implemented several newly developed technologies, pushing the limits of the industry. Challenges...

  • In contemporary architecture, glass often takes the pretentious role of something that is absent, a fully transparent, non-existent material where one can look right trough. However, a mute material that says "I'm not there" refuses to establish a relationship with the people that live in the building. This might be one of the reasons people often feel alienated in contemporary buildings.

    Neutelings Riedijk Architects follow a radical opposite path. In their projects they bend, blur color, or pour glass to make it a robust and characteristic material. A glass that tells stories,...

  • Glass is for sure a fascinating material. It is used in many projects of our practice for a long time. The talk will give an inside on what was done (including some latest projects) and what are the subjects we want to think about in the future. Since this approach has to do with cooperation as well as interdisciplinary thinking some aspects of this general ideas will be shared. Synergies can be found in many aspects of what was developed during recent years. Some of these will be highlighted.

Architectural Design, Geometries & Lighting

  • Transparency has become a new division of architectural theory and practice and has created a new kind of aesthetic sensibility, o a wealth of possibilities for visual expression The growing importance of the visual aspects in architecture is obvious, especially with respect to façades. Transparency is no longer limited to specific functional purposes (e.g. illumination of the building’s interior), but becomes a tool of formal expression itself. This raises questions regarding the theoretical/ideal/institutional background for the application of architectural glass and impacts the...

  • Monolithic glass shells can be constructed in limited sizes. Segmented shells allow coverage of larger spans. Three shell systems - spherical dome, cylindrical roof and hyperbolic paraboloid were segmented using four different curved glass segment shapes – square, diamond (or pie for dome), hexagon and hexalock. Three joint materials were analysed- glass (resulting in a monolithic glass shell), silicone (soft adhesive) and epoxy (hard adhesive). A Reissner-Mindlin finite element was used in ANSYS to discretize the modelled geometry. The boundary...

  • J. Griffith, V. Marinov, s. Marinitsch, M. Teich

    Folded glass plate structures have the potential to become the next generation of structural glass. By connecting glass plates along their edges and creating a folded plate geometry, glass can be used to transparently self-span large areas without the need for additional supporting structure. An experimental glass connection is used as a basis for this paper. Available test and numerical data is used to create an interaction diagram for this connection, giving allowable axial forces, shear forces and bending moments. Due to the dependency of folded plate structures on geometry, a...

  • Glass has been in existence for more than four thousand years. Techniques of manufacturing and design have since been under constant development. Today, we face new opportunities and challenges with respect to structural glass applications. This paper will explore objectives as to why glass is specified on building projects and outline key parameters which must be considered when designing with structural glass. A holistic approach and emerging design and construction techniques such as digital design, multi parameter optimization techniques, bar...

  • The geometric complexity resulting from the architectural pursuit of freeform structures is presenting challenges to the construction industry. Curtain wall unit system designs, for example, have morphed in some cases from predominantly flat orthogonal affairs to complex double-curvature multi-layer constructs. Many fabrication tools and processes, however, are only gradually shifting from their linear 2D roots to embrace a truly 3D fabrication environment. The validation and quality assurance of geometrically complex components is problematic in such an environment, potentially...

Curved & Bended Glass

  • Enclos is conducting ongoing research into cold formed (elastically deformed) glazing.  This paper expands on previous finite element modeling and physical testing undertaken.  The research aims to develop an understanding of surface buckling of perimeter-supported, monolithic glass that has been elastically deformed in torsion.  By extension of previous research, strategies are found to maximize the achievable twist of the glass as limited by strength or stability.  This paper includes a detailed investigation of these strategies, incorporating results from finite...

  • The fabrication of projects with complex geometries often implies a significant waste of material, since custom molds need to be created and irregular shapes need to be cut out of larger sized elements. For low curvatures, cold elastic bending processes can be applied. However, elastic bending techniques have mainly been utilized to create simple curvature panels for architectural projects. This paper explores computational simulation in relation to a digitally controlled fabrication method of bending rectangular glass sheets elastically into...

Glass in Facades

  • The evaluation of adaptive facades presents a challenge because there is no established evaluation strategy to systematically reach this goal and many of the available façade performance evaluation tools have limited applicability for such advanced building facades. This paper presents a case study for an adaptive glass façade and evaluates its performance. The evaluation focuses mainly on pre and post construction phase of adaptive facades: The design assist phase (including the durability test, visual mockup, onsite panel mounting and weather...

  • The tasks a façade has to fulfill in contemporary high-end architecture have become more and more complex and challenging. An innovative skin has to block a considerable amount of sun radiation in summer, while it has to prevent heating energy from getting lost in winter. At the same time the skin has to allow for a high amount of (controlled) natural lighting and (controlled) natural ventilation. On the other side the iconic character of “signature” architecture pushes for glass façades to become almost dematerialized, a development further reinforced by recent advances in modern glass...

  • Glazing units used for architectural applications have an enormous potential for optimization. Currently, daylight management as well as solar and shading control can be provided only through a combination of various individual elements, such as glass panes, venetian blinds and additional glare protection elements. This combination of several separate elements not only leads to a higher consumption of resources, as well as higher production costs. It also entails additional maintenance costs. In order to overcome these shortcomings, the authors have developed a switchable glazing unit...

  • Energy saving and environmental protection don’t represent only a technical problem but also, and maybe most of all, an ethical problem. From this point of view, the Mediterranean area, characterized by a considerable Sunshine for at least 8 months a year, is configured as particularly suitable for the use of all building systems that can reach the objectives provided by the latest global climate conferences. The architectural heritage of the Mediterranean area is various both in typological terms and in relation to building materials used. If you want to find materials and components...

  • Today’s green building certifications such as LEED, BREEAM, and HQE all recognize that a sustainable design is not just about energy efficiency and all integrate sections related to indoor environment quality, such as provision of natural daylight and views through windows. Yet, on the other hand, with the increasing stringency of building energy efficiency targets in Europe and indeed globally, we are observing an increasing trend to reduce window area in new building energy codes, as windows are often seen as the weak link in the building...

Hybrid & Composite Glass Components

  • Despite the great potentials of glass as a construction material, its brittle material behaviour poses major challenges to structural engineers when designing load-bearing glass structural members. This paper presents the load response and the failure behaviour of float glass–GFRP hybrid beams, when used as a mean of improving strength and ductility of float glass. Hybrid beams made from two layers of float glass sheets and an adhesively-bonded semi-transparent pre-cured GFRP interlayer were tested in four-point bending. The experimental results...

  • Safety glass is usually the proper designer choice when glazing may be subjected to the impact of a person. In order to avoid people injuries, glass products must comply with appropriate safety practices. Existing technical standards classify safety glass products by mode of breakage and post-breakage behavior. Critical demanding applications in terms of self-weight saving, like high efficiency elevator cars in buildings or aircrafts and other means of transportation interiors in aerospatial and automotive industries, are currently driving the...

  • Recent research work focused on material efficient and safe structural use of glass beams. Reinforcing and post-tensioning of those structures in the style of reinforced concrete are promising options. They allow for a safe post-breakage behaviour of load bearing glass constructions. Other ductile materials such as steel and high-grade cables strengthen the glass, which results in robust structures. However, hybrid structures are prone to temperature loads. Especially post-tensioned glass beams – Spannglass Beams – are vulnerable to lose part of their initial cable load caused by a...

  • The aim of the present paper is a preliminary assessment and critical discussion of full-scale experimental test results recently obtained for hybrid steel-glass beams composed of a laminated glass web and steel flanges, based on the analytical Möhler method. As known, the structural response of this typology of hybrid solutions markedly depends on the stiffness and resistance of all its components, and specifically the connection, which act as a flexible shear bonding layer between the glass web and the steel flanges. Therefore, the appropriate...

  • The mechanical performance of photovoltaic modules has not been adequately characterized for use as glazing product in the building envelope. As a result, the modules are subject to individual approval by the building authorities in many building-integrated applications. This paper presents experimental research on glass based photovoltaic modules, analyzing their mechanical properties in comparison with regulated construction products. The focus is on the influence of photovoltaic thin-film coatings on the bending strength of the float glass used as a substrate or superstrate and on the...

  • Intensive progress in the field of polymer adhesives opens up new opportunities in their usage. Glass is combined with steel in hybrid systems to improve its load-bearing capacity, stiffness, residual load-carrying capacity and to preserve a high degree of transparency at the same time. Adhesive connection between glass and other materials in hybrid structures is beneficial, because in dependence on geometry and stiffness, the glue in joints can provide uniform stress distribution along the contact area. The current paper deals with the research...

  • Developed by seele for industrial and commercial buildings, iconic skin glass sandwich panel (GSP) is a novel glass panel façade that meets high-level design and economic demands. The idea is to merge two established façade products into a new one: The glass sandwich panel consists of an outer printed glass sheet bonded to a standard sandwich panel. This creates a glass exterior in the form of panels up to a height of 15 m. These huge formats allow architects to employ glass sandwich panels to create homogeneous and flush façade surfaces in...

Insulating Glass Units

  • The increasing demand for use of laminated glass in building facades is the driving force for new interlayers testing and their implementation. Architects’ and engineers’ requests require searching for new solutions and processes of lamination. Intelligent facades, electrochromic windows, integrated photovoltaics, integrated lighting, enhanced solar control, acoustic pollution reduction, wires incorporation, use of special sealants and glues are some of the design drivers of new laminated structures.

    Laminated safety glass is composed of two or more glass panes bonded by one or...

  • For the use in structural glazing (SSG) applications a new generation of warm edge system has been developed. This new technology is a spacer system based on polyisobutylene, especially designed for silicone sealed units, which replaces the conventional edge seal components: metal or plastic spacer, desiccant and primary sealant.  In contrast to these components, this hot applied spacer system is an integrated polymer matrix incorporating the desiccant, which meets the high requirements regarding long term stability and in particular the demands for noble gas tightness of insulating...

  • The saving of energy has been an important topic for the last years. However, not only for building constructions but also in the field of naval architecture the energy revolution affected the used materials. Insulation glass units (IGU) are used on ships, because of their increased thermal insulation value, but their known problem of durability remains. Already after a few years, naval insulating glass units fog up on the inner site of the glass panes and get unusable. The insulating glass units are exposed to higher stress in the naval environment compared with building constructions....

  • Climatic loads on Insulated Glazed Units (IGU) have been investigated since the early 1990s. Beginning in 1996 a German technical guideline defined the procedure to respect climatic loads in static design of IGUs. Furthermore the required values of climatic changes and thermal changes of Double Glazed Units (DGU) have been determined. In practice, those values have been applied to other systems like Triple Glazed Units (TGU) as well as Double Skin Facades (DSF). In the last two decade’s those values haven not changed. This paper presents the results...

Joints, Fixings & Adhesives

  • P. Descamps, J. Kimberlain, J. Bautista, P. Vandereecken

    Bonding of glass onto aluminum frames, known as “Structural Silicone Glazing”, has been applied for more than 40 years in glass curtain wall facades. Silicone sealants are being used in this application because of their outstanding resistance to weathering (UV, temperature, moisture, ozone), They also provide resistance to water egress and thermal insulation. Their role, structurally, is to resist to windloads and to compensate for differential thermal expansion of glass and aluminum frame. For windload resistance, silicone bite is calculated using...

  • Façade failure due to seismic event represents a potential hazard to people and can cause serious damages to buildings with consequent high-cost remedial works. As a result, interest in the design of buildings and façades to resist seismic loads and displacements has increased. Current standards and literature recognize the benefits offered by Structural Sealant Glazing (SSG) systems to enhance the performance of unitized curtain walls exposed to earthquake but no precise criteria are available for the seismic design of the structural silicone...

  • This study assesses the shear strength of long adhesive joints on mid-size specimens to resemble virtually a life-size situation in a typical timber-glass composite element. The specimens comprise a rectangular glass pane which is adhesively bonded along its vertical edges onto timber posts. The study focuses on three different adhesives ranging from flexible silicones to viscoplastic epoxies with a high stiffness. In the experiment, the adhesive joints are stressed in longitudinal shear and loaded until failure.The experiment is simulated using a...

  • Architectural trends have tended towards curved glass envelopes and maximised transparency by reducing solid fixing areas. One approach towards transparent glass connections is a heat bonding process based on the principles of welding. This paper investigates the level of residual stress in soda lime silica and borosilicate glass caused by a heat-based connection or forming process. Nominal levels of residual stress prior to heat impact, directly after heat impact and after annealing will be measured on small-scale samples, utilizing a scattered light polariscope (SCALP). Material...

  • M.A. Samieian, D. Cormie, F. Doebbel, D. Smith, W. Wholey, B.R.K. Blackman, P.A. Hooper, J.P. Dear

    An experimental study has taken place to quantify the strength of single sided structural silicone glazing joints under blast loading. The structural silicone specimens in this experiment were tested using a high-speed servo-hydraulic test machine at varying rates, representative of that experienced in a blast. Tests were conducted at displacement rates of 1m/s, 2m/s and 4m/s. The load was applied at two different angles of 30° and 45°. The tests were carried out on samples with different bite depths. The load was measured and the strength of the silicone joint was calculated at...

  • SentryGlas® (SG) (a transparent ionomer from Kuraray) and Transparent Structural Silicon Adhesive (TSSA) (a transparent silicon from Dow Corning) are two of the adhesive materials used in laminated adhesive connections for structural glass applications. Although they have been used in several projects worldwide, failure criteria for these materials are currently not available in literature. This work gives an introduction to the theoretical development of a novel failure a criterion for TSSA and SG under varying stress state conditions. The main output of this work is a...

  • The determination of load carrying capacity and serviceability of point fixed glazing is a challenging task. A lot of parameters have an influence on the resulting values, especially on stress values around the bore hole. Generally, only specialized engineers are able to perform this analysis. Reasons for this are the multitude of parameters, the lack of analytical solutions and incompletely analyzed load carrying mechanisms on the one hand, and on the other hand, the lack of a generally accepted and accurate design concept for stress and deflection...

  • There are different options to obtain a structural glass beam with a span of more than 6 meters. One option is segmentation, which has many advantages compared with the other options. However, the choice for segmentation is often avoided, because of aesthetic reasons. Existing connections, even the most slender ones, result in a reduction of the transparency of the beam. While transparency is the key reason to use glass beams. In this paper a connection is presented that should improve the transparency of segmented glass beam. The connection is...

  • In façade applications, structural sealant glazing systems with a soft adhesive like silicones show a number of advantages especially regarding brittle adherends like glass sheets, as stress concentrations in the adherends are avoided due to the large bonding area and the uniform load transfer. The application guideline for structural sealant glazing systems (European Technical Application Guideline ETAG 002) defines a simplified design concept for the silicone sealant, leading to high safety factors and restrictions in use. The material behaviour of the silicone sealant can be more...

  • During recent years, adhesives are more frequently used for glass applications in buildings, and according knowledge on adhesive glass-metal connections increased exponentially. However, further research regarding the performance of such connections remains indispensable to further optimise existing concepts or to develop and implement new technologies. To analyse the mechanical behaviour of adhesive glass-metal connections, computer simulations based on the finite element method can be performed. To do so, material properties of all components have...

  • Abstract: SentryGlas® foil has been used for over a decade as a laminating foil but also to bond metal inserts to glass. Most famously in the Apple cube and other Apple buildings and staircases. Although the joint is transparent and statically strong, little is known about the long term behaviour. Specimens were prepared of perforated stainless steel and glass. These were laminated using SentryGlas® foil. Tensile tests, fatigue tests and creep tests were conducted at room temperature and  additional creep/fatigue tests at 40⁰C. The results are...

Laminated Glass & Interlayer Properties

  • Many studies reported in the literature are able to demonstrate significant influence of weathering on physical and mechanical properties of PVB. In this paper, the results of these researches are compared and discussed. The effects of rheological parameters modifications on the coupling capability of laminated glass structural elements and on the mechanical response to loads are then evaluated through numerical analysis. Real structures are often exposed to direct sunlight or to temperature or humidity levels that can induce damage phenomena in the interlayer; the modification of...

  • Design and structural performance of laminated glass in over-head glazing applications like canopies, skylights is very critical as it has an impact on the safety of occupants of a building and its maintenance workers. For such applications post breakage strength of laminated glass construction is of utmost importance. Pre breakage strength can be predicted with reasonable accuracy by FEM technique based software packages, which allow the user to input mechanical properties of viscoelastic interlayers along with glass. This helps in interlayer based differentiation of pre breakage...

  • The proper measurement and interpretation of modulus data for glass laminate interlayers can be quite complex. The development of master curves using different deformation modes and the preparation of the samples for measurement can significantly affect the results. International standard ISO 6721, determination of dynamic mechanical properties, uses modulus as a primary criterion for method selection. The shear modulus of polyvinylbutyral (PVB) materials varies to a great extent, e.g. 1 – 400 MPa, over the temperatures and durations encountered for glass laminates in a building. We...

Numerical Modeling & Experimental Validation

  • Annealed glass has a high compression resistance but it is fragile and its tensile strength is low due to the random distribution of surface flaws and impurities, which induce cracks without prior warning and each crack is regarded as a failure. This phenomenon is dependent on surface micro-defects in the glass due to inclusions within the glass or to scratches caused by normal use and by the shaping process. Classical four point bending tests are not suitable for glass plates, because of the test’s configuration, the maximum stress is reached on the plate edges where, due to the cutting...

  • Glass with a thickness of 0.55 up to 2.0 mm can be defined as a thin glass or even as ultra-light. On the market there are several suppliers, which offer such thin glass. On the one hand there are e.g. Gorilla Glass produced by Corning Incorporated or Leoflex by AGC, which are pre-stress by chemical treatment and on the other hand there are soda lime silicate glass products, which are pre-stress by thermal or chemical treatment. Not only the design with thin glass causes a totally new kind of thinking, also possible test scenarios for determination...

  • J. Pelfrene, S. van Dam, J. Kuntsche, W. van Paepegem

    In modern-day architecture, transparent glass units are omnipresent as large façades, windows, floors and balustrades. To ensure safety in an accident, glass panels must successfully pass the 'human impact' test, described by the international standard EN 12600. This test setup consists of a steel frame in which the test plate is clamped with prescribed force; and the pendulum impactor, hanging from a steel cable. The impactor weighs a total 50 kg and is built up from a rigid steel core to which two small tyres are mounted. The window panels are assigned a qualification number as they...

  • J. Pelfrene, S. van Dam, R. Sevenois, F. Gilabert, W. van Paepegem

    In finite element simulation of glass cracking for practical engineering problems, the method of element deletion is often used despite its shortcomings. With this technique, an element is removed from the system upon reaching a certain failure criterion. Many different formulations for the failure behaviour of an element are possible, differentiated by the physical correctness of their representation and by their implications on the numerical stability of the calculation. In this paper, three failure models are characterised by use of a unit element model and evaluated for the drop...

Projects & Case studies

  • The design of the structural glass for the Manchester Town Hall Link (completed 2015) was carried out by engineering consultancy Eckersley O’Callaghan (EOC).  The glass facade forms an enclosed shell which supports a steel roof and acts monolithically to resist lateral loads.  The project collates the latest advances in glass technology combined with innovative design methods.  In the absence of explicit codes of practice for structural glass, EOC performed a first principles approach in using empirical data, acquired through previous projects, and analytical methods,...

  • ZJA Zwarts & Jansma Architects have designed a new departure light rail station in The Hague, Netherlands. The spatial roof structure of the station is made of rolled rectangular steel hollow sections, arranged in two independent layers rigidly connected to each other. A glass envelope covering the roof structure is matching the contours of the steel exactly. Since the diamond shaped glass panels can only be attached to the outer layer of the steel grid, the glass with edge lengths of approximately 1,30m is two-side supported. When optimizing...

  • T. Herrmann, S. Siebert

    In January 2015 a pavilion mainly built of glass was finished. The building contractors themselves planned it as a transparent extension of their detached house to the garden. The structural system consists on one hand of a glazed steel frame with four stanchions rigidly fixed to the base plate and connected by four transoms at the top and on the other hand of two laterally glass attachments. These are made of vertical load-bearing glass walls and a horizontal glass roof, which are connected among each other by structural sealants. Together with an anchor profile that is completely...

  • B. Kassnel-Henneberg

    Enclosed envelopes without any visible supporting structure or stairs which seem to float on air are the dreams of many architects and designers. Glass is one of the few materials that can allow this dream to become a reality. For this reason full glass structures can appear to be practically invisible and the observer experiences the wonderful sensation of seeing a floating, weightless and totally transparent structure, as if it's almost not there. To fulfill these demands but also to enable the integrity of the whole glass structure, the connections between the elements represent one...

  • The „Ostwall“, one of Krefeld‘s most important public traffic intersections, is getting modernized completely for the moment. The highlight of the project is the new canopy for the tram and bus stop. It was decided to realize a steel-glass structure, to get most possible transparency. The structure has a length of 125m and a width of 12m. The main structure has 9 column brackets, that are bearing a space truss. These elements are made of steel. For the roofing, partially curved glass elements are used, that are bonded to a stainless steel frame by structural silicone. The slope of the...

  • For the design of the Visitor Centre of ‘Park Groot Vijversburg’ at Tytsjerk, The Netherlands, the limits of structural design are examined, resulting in one of the largest glass bearing structures. The architectural design is by Junya Ishigami and Marieke Kums of Studio Maks. In plan, the shape of the Visitor Centre is as that of a triangle being pulled firmly in three directions while maintaining a central hall. The architectural design exists of a glass façade with roof only. During the design it became clear that it was the architect’s wish not...

  • This paper illustrates the design process and the load testing of a steel-reinforced laminated glass beam built for a 6 m span glass footbridge. This specific glass footbridge has been designed and tested to join two existing floors of the main room of a refurbished masonry building of the 19th century public slaughterhouse of Pisa. To meet the needs for transparency asked by the Municipality of Pisa the beams, the running surface and the balustrades, were made of laminated glass. The project started with a design of a 5790 mm length beam which has been designed and checked...

  • The paper illustrates the project for a structural glass walkway that will connect two important historical buildings in Pisa, Palazzo delle Logge di Banchi and Palazzo Pretorio, which are currently used as administrative offices by the City Council. The entire project is developed with particular attention to the conservation of those buildings, the idea is to build a transparent glass footbridge that does not distract people’s attention from the surrounding buildings. The pedestrian walkway has a span of 9.15 metres over the main pedestrian and commercial street of Pisa. In order to...

  • F. Oikonomopoulou, T. Bristogianni, F.A. Veer, R. Nijsse

    This paper presents the main challenges confronted during the construction of the innovative Crystal Houses façade in Amsterdam. Designed by MVRDV and Gietermans & Van Dijk architectural offices, the façade is a transparent reproduction of the previous 19th century masonry elevation, entirely made of adhesively bonded solid glass bricks. Even the window and door frames are reinterpreted by elaborated massive cast glass components. To obtain pure transparency, the resulting 10 m by 12 m glass masonry wall should be self-supporting. To achieve the...

  • Inspired by the glass masonry technique developed by the TU Delft Glass and Transparency Lab for the Crystal House in Amsterdam, a 14 meter span pedestrian bridge is envisioned, also consisting of cast glass elements.  In contrast to the Crystal House project that employs an adhesively bonded glass block system, here dry assembly of the glass elements is proposed to allow for a demountable structure. To achieve this, a constant compression force is introduced in the bridge through its arch-shape. This compression force and a special interlocking geometry of the blocks will ensure...

  • T. Wever, K. Haarhuis, E. ten Brincke, R. Nijsse

    In projects involving swimming pools with structural glass, ABT Consulting Engineers has faced similar design requirements: maximal transparency, proper detailing, 100% water tightness and robust behavior. ABT developed a straightforward detailing to satisfy these requirements. The concept is applied in the glass swimming pool of the 900 Mahler project, where the layered and heat strengthened glass panes were designed with specific attention to the appropriate type of interlayer and functional, durable and practical support detailing. The...

Stability & Strength

  • In current practice, glass shear walls are frequently used to cover wide surfaces in facades. There, a multitude of restraints can be found, depending on specific aesthetic, architectural and structural requirements. Typical practical examples can in fact take the form of linear adhesive joints, metal frames or mechanical point fixings, etc. From a practical point of view, as a result, it is clear that compared to idealized boundary conditions the actual restraints should be properly taken into account. In this research paper, the shear buckling response of glass shear walls is assessed...

  • Kyriaki Corinna Datsiou, Mauro Overend

    Surface damage that accumulates on the surface of glass is known to govern the strength of this material. It would therefore be very useful to use artificial ageing techniques to replicate this level of damage; this would allow a rapid and cost effective assessment of the expected glass strength and the long term performance of novel glass products and treatments. Some artificial ageing methods exist but it is unclear whether the surface damage induced is correlated with the physical damage found in naturally aged glass. The aim of this paper is...

  • The applicability of the Weibull distribution to model the strength of glass, the existence of a size effect on the strength and the need for a non-destructive testing of the strength are discussed and reviewed. There are a growing number of studies that put into question the applicability of the Weibull distribution to model annealed glass fracture data. A recent study indicates that the breakage stresses are uncorrelated with the surface area, in violation of the size effect which entails the Weibull model. It is shown in this paper, however, that there is a size effect, as evidenced...

  • Bernhard Weller, Katharina Lohr, Michael Engelmann

    Designers use exposed glass edges for decoration, for example within glass steps, glass beams or glass columns. This application requires a mechanical finishing to achieve a high optical quality by compensating a misalignment of the glasses, for example an edge displacement, or a supernatant of the foil resulting from the lamination process of safety glass. Regrinding of annealed glass is allowed without restrictions. In the case of tempered glass there is a risk of premature failure caused by a reduction of the compression zone. During a research...

Structural Glass Design Philosophy & Structural Safety

  • Glass has been used as a prized construction material for centuries.  Typically it has been used as a window infill, initially designed empirically where thickness available was adequate for the sizes available.  As technology has proceeded, the size of glass available has increased by orders of magnitudes and standards have been written to guide the design in windows.  Glass remains unique amongst the construction materials, that failure and replacement is considered an acceptable price to pay for the transparency of glass. The same logic has, however, limited the use of...

  • The new German Glass design standard DIN 18008 – parts 1 to 5 – was finally established in the beginning of 2015, being accepted by the authorities already a few months earlier. As the application is obligatory since then, a lot of experience could be gained in the meantime. Every standard has to pass several steps of control and revision before being approved. Nevertheless the actual application brings up new aspects and questions about certain details and the corresponding interpretation and intention of the standard. The following paper will discuss some important aspects of DIN 18008...