EXPLORING THE POTENTIAL OF FREE STANDING GLASS COLUMNS ASSEMBLED FROM STACKED INTERLOCKING CAST ELEMENTS
This paper presents the research conducted on free standing glass columns assembled from stacked interlocking cast elements. Glass has a compression strength exceeding that of concrete, constituting the concept of a glass column unique, considering the transparent design opportunities. However, due to the brittle nature of glass, safety is hard to guarantee in glass columns and there are thus only few realized examples. On the basis of structural safety, this research explores the potential of an innovative type of column of increased transparency and structural redundancy. As a case study, the replacement of the two existing concrete columns in the Berlage lecture room in the TU Delft Faculty of Architecture is proposed. In specific, 54 cast glass units of maximum 10Kg mass each, are stacked on top of each other to form a 6m high column. To allow for an easy assembly and disassembly, an interlocking shape for dry-stacking is designed, with a clear PET interlayer in-between to prevent the generation of peak stresses. Emphasis is also given to the connection detailing. As a proof of concept, 9 components are kilncast and tested under compression. The results demonstrate the structural and aesthetic potential of the designed column.
PRODUCTION AND TESTING OF KILN-CAST GLASS COMPONENTS FOR AN INTERLOCKING, DRY-ASSEMBLED TRANSPARENT BRIDGE
A pedestrian glass bridge, located at the TU Delft campus site, is designed by the TU Delft Glass & Transparency Lab. The arch-formed bridge consists of cast glass, dry-assembled, interlocking components. To validate the components’ shape, glass mock-ups are kiln-cast and tested. This paper follows the elements’ production process from the milled MDF model and the construction of disposable moulds via the lost-wax technique, to the kiln-casting at 940C with the flowerpot method. Steps are taken towards the refinement of the production technique, with emphasis in minimizing the occurrence of air bubbles, surface flaws and internal stresses that reduce the load-bearing capacity of the components. Polarisation techniques are employed to define the residual stress distribution of the cast elements as well as to map the consolidated flow of molten glass and the areas of inhomogeneity or non-cohesion. The structural performance of the components and the interlocking system is studied by conducting a 4-point bending test on an arch specimen comprising 20 glass bricks with a transparent PU interlayer in-between. The results are compared with similar tests conducted with glass units produced by other methods, such as waterjet cutting or hot-pouring.
Company:TU Delft, Faculty of Civil Engineering and Geosciences
Short Bio:Bristogianni Telesilla is a PhD researcher in Civil Engineering at the Glass and Transparency Lab of TU Delft since 2014, focusing on structural cast-glass elements. She has a background in architecture and building technology, with a specialization in performance driven design and the development of novel building components with the aid of parametric models and digital simulations, and supported by material research and the production of physical prototypes.