1,720,991 research outputs found
Corrugated glass as improvement to the structural resistance of glass
Get PDFp. 3052-3064It is a well known fact that if we take a flat piece of paper in our hands it is a weak, and
slack.. However if you fold this piece of paper a few times the structural behaviour changes from weak to strong and form slack to stiff. .Luckily enough the glass manufacturing firms are more and more capable to create folded,or better, corrugated glass. Therefore we have started to create glass structures in corrugated glass. Two well known buildings have incorporated corrugated glass in their facades. They are the Casa da Musica in Porto (P),(architect OMA) and The Museum aan de Stroom (MAS) in Antwerp (B), (architect Neutelings Riedijk). Two other projects are on the drawing boards; the University Library in Qatar (architect OMA) where a diamond shaped building has on four sides large facades composed by corrugated, insulated glass units up to a height of 17 meter and a villa in NL by MVRDV architects where corrugated insulated glass units carry the roof. In these four buildings the corrugated glass panels are used to create, with a relatively thin sheet of glass an all glass facade without hardly any steel components..Nijsse, R. (2009). Corrugated glass as improvement to the structural resistance of glass. Editorial Universitat Politècnica de València. https://riunet.upv.es/handle/10251/671
Through-cracked tensile delamination tests with photoelastic measurements
No full textThe critical mechanism in the post-glass-breakage response of laminated glass is delamination of polymeric interlayer from glass shards. To investigate adhesion properties between glass and PVB, "Through-Cracked-Tensile" tests have been performed at room temperature, with different stain rate and polymer thickness. Using photoelastic properties of PVB, the stress has been detected during the test, while measuring force-displacement and force-delamination diagrams. Two different failure modes have been recognized, influenced by the presence of friction while relative sliding between the two materials occurs. A steady delamination takes place only when friction is not present; on the other hand, friction can arrest delamination, and the interlayer eventually breaks. Results have been interpreted though a minimal model that predicts the delamination load
Dematerialization of the Ruins: Glass as a Promising Restorative Material for the Consolidation of Historic Structures
No full textThis research investigates the potential of glass as a new design tool to highlight and safeguard our historic structures. Current restoration and conservation treatments with traditional materials bear the risk of conjecture between the original and new elements, whereas the high consolidation demands often result in visually invasive and irreversible solutions. Nowadays, aspects of materiality and aesthetics appear as integral parts of the restoration practices, indicating new materials and technologies in the form of ambiguous gestures rather than absolute and permanent manifestations that prevail over the historic structures. The inherent transparent properties render glass a distinct material that enables the simultaneous perception of the monument in both its original and ruinous state. The emerging technologies have set the ground for using glass in a structural way minimizing the need for substructure and maximizing transparency, while protecting the sensitive historic materials. The paper explores the feasibility of this concept addressing aspects of compatibility, reversibility and transparency, through a review of realized examples. Finally, a developed methodology relates the, available in the market today, glass products to the possible consolidation treatments in respect to the degree of intervention and representativeness, stressing the potential of using and considering glass as a promising restorative material.Applied MechanicsStructural Design & MechanicsOLD Structural Desig
Structural Strength of Laminated Glass
No full textThe subject area "structural strength of materials" is defined generally as а complex of strength characteristics of materials and structural elements, obtained under special mechanical tests. It is shown that these tests should take into account not only the physical and mechanical properties of the material, but technology, blank processing, sphere of application, the influence of shape and sizes of elements as well as of their specific loading and operating conditions. Methods for evaluating the structural strength of glass as a linearly elastic material with high sensitivity to technological defects and operational damage are discussed in the paper. Some results of the study of the strength of elements of architectural and bulletproof laminated glass are given. The sizes of technological defects such as cracks in large-sized building elements are determined on the basis of the results of tests of sheet glass plates on bending. The bending strength of sheet float glass with a thickness up to 10 mm reinforced with modification of the glass surface using various industrial technologies is considered. Some methods and results of experimental study the features of the change in the strength and rigidity of laminated armored glass under multiple ballistic tests are also presented.Structural Design & Mechanic
Vacuumatics: 3D formwork systems : Investigations of the structural and morphological nature of vacuumatic structures so as to be used as semi-rigid formwork systems for producing 'free forms' and customised surface textures in concrete for architectural applications
Get PDFOne of the most important architectural trends of the last two decades is commonly referred to as ‘digital architecture’. This trend comprises digitally-generated geometrically complex, often irregular, yet fluent double-curved shapes (or rather ‘free forms’) in architecture. Although advanced digital manufacturing systems are emerging in architecture, the construction processes in general require some sort of boost to ‘keep up’ with the already heavily advanced (digital) design and analysis processes. Curable materials (such as concrete) are considered particularly useful for the realisation of the desired ‘free forms’. The formability and the adaptability of the formwork system of choice, however, are typically considered the limiting factors. Previous research by the author has indicated the potential of so-called vacuumatic structures (or simply ‘vacuumatics’) to be used as semi-rigid formwork systems. Little is known, however, about the specific structural properties and to a lesser extent the morphological formability of these types of structures. Vacuumatic structures typically consist of an (unbound) aggregate core, which is enclosed by a flexible membrane envelope and structurally stabilised by means of an internal underpressure. The research presented in this thesis aims at defining the influence of the individual characteristics of the aggregate core and the membrane envelope on the overall flexural behaviour of vacuumatic structures. Furthermore, the basic structural mechanics is explored with which the flexural behaviour of vacuumatic structures can be explained. Apart from that, this research aims at defining which shaping techniques are considered most effective for using vacuumatic structures as semi-rigid formwork systems for producing ‘free forms’ and customised surface textures in concrete for architectural applications
A Novel, Demountable Structural Glass System Out of Dry-Assembly, Interlocking Cast Glass Components
No full textCast glass components are a promising solution for engineering pure glass structures of high transparency and load-carrying capacity due to their large cross-sectional area and monolithic nature. Currently, the few realized structures employing cast glass components rely either on a steel substructure or on an adhesive of high bonding strength and typically less than 2 mm thickness, to ensure the stiffness and stability of the construction. Whereas the first solution compromises the overall level of transparency, the second results to a permanent construction requiring intensive and meticulous labour and extreme accuracy. This paper explores the potential of a novel, reversible all-glass system comprising dry-assembly, interlocking cast glass components as a promising and sustainable solution that can avoid the above-mentioned challenges. Owing to its interlocking geometry, the proposed system can attain the desired stiffness and stability with the aid of minimal, if any, metal framing. Furthermore, the suggested system circumvents the use of adhesives by using a dry, colourless interlayer as an intermediate between the glass components to accommodate any dimensional tolerances and allow for an even load distribution; moreover, it allows for the disassembly and circular use of the components. To validate the concept, different component geometries and interlocking mechanisms are developed. As a proof of concept, the most promising interlocking forms are kiln cast in 1:2 scale and assessed in terms of mechanical interlocking capacity, mass distribution, residual stress generation and ease of fabrication. In parallel, research is conducted on different materials for the dry, transparent interlayer. From the developed designs, blocks with osteomorphic interlocking mechanisms are selected as the most promising concept and are further assessed by numerical modelling to study the influence of the interlocking geometry to the overall structural performance. The results highlight the structural potential of the proposed system and demonstrate its feasibility.Structural Design & MechanicsApplied MechanicsOLD Structural Desig
Flexible Transparency: a Study on Adaptive Thin Glass Façade Panels
No full textChemically strengthened thin glass (t < 2 mm) is a material that is stronger and due to its small thickness, more flexible than conventional window glass. As such, thin glass offers the possibility for lightweight and flexible glass façades that could change shape depending on external conditions. This paper explores this concept and presents an MSc study on the use of this material in adaptive façade panels. The behavior of thin glass in this context depends on different factors. The glass thickness and strength define its bending limits, while the desired geometry and movement affect its overall stiffness and visual outcome. In order to integrate these factors, different configurations of panels were analyzed in numerical models. These analyses showed the importance of understanding the desired movement and geometry in order to correctly define the supports and degrees of freedom of the panel, avoiding stress concentration (particularly on the edges) and allowing for an unobstructed movement of the panel. The development of these analyses resulted in the conception of a design example of an adaptive façade panel, taking into consideration the design requirements developed in the research. Finally, as a proof of concept, a mock-up was built simulating the behavior of the design example developed in this research. Although there is still the need for research to be developed so that thin glass can become a building material, this research showed that this is possible and that interesting results, regarding visual effect, ventilation and dead load reduction (in larger scale, an environmental impact reduction is also possible) can be achieved. Besides that, using thin glass in adaptive panels challenges the concept of glass as a static material, opening new possibilities for its use.OLD Structural DesignBuilding Product Innovatio
Building and Testing Lenticular Truss Bridge with Glass-Bundle Diagonals and Cast Glass Connections
No full textOn the campus of Delft University the Glass and Transparency Research Group is preparing to build a pedestrian bridge as a low arch consisting of dry-stacked glass blocks. As temporary support for the arch, a lens-shaped truss has been constructed and placed on location. This truss has been fitted with as many glass components as was structurally feasible. The diagonals in the truss are glass bundle struts and the nodes of the truss are cast glass components. The lenticular truss will serve as a temporary bridge during the time the team needs to prepare for construction of the eventual Glass Arch Bridge. Due to the experimental nature of the truss, with its unusual and novel applications of structural glass, a number of demonstrative proof loadings were performed to ease concerns about the safety of the structure. The glass bundles have been proof-loaded to twice their maximum expected load just prior to their installation in the structure. The whole system has then been proof-loaded for several critical load combinations (static and dynamic) just after installation. During the proof-loading the strains in the glass diagonals have been measured. These lie easily within the acceptable limits. In the paper the structural design of the bridge, in particular the glass node connector and the glass bundle diagonals will be explained. Then the proof-loading of the bridge will be described. Then the results of the proof-loading are presented and discussed.OLD Structural DesignApplied Mechanic
Design and Experimental Testing of All Glass Sandwich Panels: An Experimental and Numerical Study for the Glass Floors of the Acropolis Museum
No full textThis paper describes the engineering steps taken in order to investigate the potential of glass sandwich elements, made of 2 glass skins separated by a glass core in the form of spacers, as a way to create planar elements with a high stiffness to weight ratio, reducing material consumption in structural glazing applications. The aim is to explore and evaluate the optical quality and the structural performance of those elements. In this research, 7 core topologies are explored in order to define which parameters influence the behaviour of a sandwich structure made completely with glass. From those topologies, one is chosen to be explored further. The said topology is optimised to make the panels more efficient in terms of stiffness and weight reduction. In order to determine the structural behaviour (strength, stiffness, failure modes) of the elements, 4-point bending tests are conducted on 9 specimens in total. Finally, in order to define the aesthetical and structural requirements of such a project, the replacement of the glass floors of the Acropolis Museum in Athens in Greece is used as a case study. The knowledge acquired through this process is used to optimise the panels of the new glass floors taking also into account other parameters related to transparent flooring e.g. optical quality, psychological factors, anti-slip resistance etcStructural Design & Mechanic
Edge-laminated Transparent Structural Silicone Adhesive (TSSA) Steel-to-Glass Connections
No full textThe connections between glass components are very critical aspects of structural glass design. Laminated steel-to-glass connections have recently been developed that combine high strength and transparency. This work focuses on the Transparent Structural Silicone Adhesive (TSSA), produced by Dow Corning. TSSA is typically used for the realization of circular point connections on the glass surface. An alternative approach of using TSSA is considered in this study, by laminating stainless steel connectors on the edge of the glass. These connections are experimentally and numerically investigated. The edge bonded specimens are tested in shear and the stress distribution of the adhesive is analyzed by means of a three-dimensional finite element model. The distribution of stresses in the adhesive is non-linear showing significant stress peaks towards the free edges of the adhesive. A parametric study is conducted to relate the magnitude of the shear stress peaks and bending stresses with the eccentricity of the applied load. The occurrence of failure at lower engineering stresses than the ones recorded for circular point connections is explained using the theory of bending-shear interaction laws. Based on these failure criteria, shear stress peaks that occur due to the eccentricity of the applied load have an important influence on the global resistance of the connection.OLD Structural Desig
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