Keywords

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Cast glass, Structural glass, Glass recycling, Glass waste, Reuse, Architecture, Casting, Glass structures, Glass bricks.

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Project duration

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2017 - present

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Initiated by

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Ir. Telesilla Bristogianni (CiTG)
Dr. ir. Faidra Oikonomopoulou (BK)

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Research Team

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Ir. Telesilla Bristogianni (CiTG)
Dr. ir. Faidra Oikonomopoulou (BK)
 

Collaborators

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Material sponsored by Vlakglas, Maltha Recycling, AGC

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About

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It is only in the last decades that the structural potential of glass has started to unveil. Combining transparency with a high compressive strength, glass enables us to make diaphanous load-bearing compressive members, from beams and columns to free-standing facades and entire glass structures. Although glass’ fabrication boundaries have been continuously stretching, so far, glass structures are still confined to the shapes and dimensions that can be realized by the virtually flat elements fabricated by the float industry. Moreover, despite the fact that glass is fully recyclable, the majority of glass objects are neither reused nor recycled, mainly due to contamination from coatings and adhesives.

Cast glass can escape the design limitations generated from the 2-dimensional nature of float glass. By pouring molten glass into moulds, solid 3-dimensional glass components can be obtained of virtually any shape and cross-section. 

Owing to their large cross-sectional area and monolithic nature, such components can form repetitive units for the construction of 3-dimensional, free-form glass structures that do not buckle due to slender proportions, taking full advantage of glass’s high compressive strength and sparing the necessity of an additional supporting structure. The Crystal Houses façade in Amsterdam, designed by MVRDV and developed by the TU Delft Glass & Transparency group, forms the current state-of-the-art in the field of architectural cast glass. The cast block façade, bonded by a rigid, colourless adhesive of virtually zero thickness, manifests the potential of cast glass in architecture but also points out the engineering challenges resulting from a permanent construction of extreme accuracy and intensive and meticulous labour. 

Grasping this potential, the “Re3 Glass” project introduces a novel, reversible system comprising dry-assembled, interlocking cast glass components in respect to the waste hierarchy of Reduce, Reuse and Recycle. 

Re3 Glass can tackle the challenges generated by the aforementioned system and enable the circular use of the glass components, through the following threefold Re3 approach:

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Step 1. REcycle by employing waste glass: Although in theory glass can be endlessly remelted without loss in quality, in practice only a small percentage gets recycled, mainly by the float and packaging industry. Most of the discarded glass fails to pass the high quality standards of the prevailing glass industry -due to coatings, adhesives,  other contaminants or incompatibility of the recipe-  and ends up in the landfill. Employing discarded glass in cast components can be a way to reintroduce this waste to the supply chain. Cast glass units–due to their increased cross section– can tolerate a higher degree of impurities and thus can be produced by using waste glass as a raw source, without necessarily compromising their mechanical or aesthetical properties.

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Step 2. REduce by implementing smart geometry: Smart geometry is implemented in the form of cavities and notches, to achieve lightweight yet strong components that reduce not only the required raw material but also the overall embodied energy.

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Step 3. REuse by designing interlocking components: Through an interlocking geometry, the proposed system can attain the desired stiffness and stability with the aid of minimal metal framing. Furthermore, the new system circumvents the use of adhesives by using a dry, colourless interlayer as an intermediate between the glass units. Besides preventing stress concentrations due to glass to glass contact, the dry interlayer can also accommodate the inevitable dimensional tolerances in the cast units’ size.  Most important, a dry interlayer allows for a reversible glass system and for the circular use of the components.

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To validate the concept, different component geometries have been developed and kilncast by the Glass & Transparency Group of TU Delft and assessed in terms of mechanical interlocking capacity, mass distribution and ease of fabrication. The structural performance of the interlocking components is validated by both numerical models and physical testing of the kilncast prototypes. 

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Different materials, (e.g. PVB, PU) and production methods for the dry, transparent interlayer have also been experimentally assessed. Series of experiments on different glass types, from beer bottles and Pyrex® trays to mobile phone and computer screens, open new possibilities for the recycling of everyday glass waste into structural glass components. 

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Outcome of the “Re3 Glass” project is the new generation of REcyclable, REducible and REusable cast glass components, proposing an innovative and sustainable way of building with diaphanous structural components. 

Re3 Glass has been exhibited at the Venice Design 2018 , the Dutch Design Week 2018 and the Milan Design Week 2019. A selection of Re3 Glass components are exhibited at the Schaudepot Lab, Vitra Design Museum. For its innovative use of waste glass and circular approach, Re3 Glass has been nominated for the New Material Award 2018 and the STARTS Prize 2020. Re3 glass is currently exhibited at the topics media station of the Parlamentarium – The European Parliament’s Visitors’ Center in Brussels – representing the topic of “Climate Change”. 

 

Re3 Glass has been selected to represent the theme of climate change, one of the 5 key topics on the Parliament’s political agenda, at the topics media station of the Parlamentarium - the European Parliament's Visitors' Centre in Brussels;. The project is showcased amongst leading innovations such as the Covid-19 vaccine (Health topic) and a miniature reproduction of a quantum computer (Digital transition topic).

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Funded by

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4TU. Bouw Lighthouse 2017

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Publications 

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• T. Bristogianni, F. Oikonomopoulou, R. Yu, F. Veer, R. Nijsse, 2020. Investigating the flexural strength of recycled cast glass. Journal of Glass Structures & Engineering, accepted on 08/09/2020, under publication.

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• R. Yu, T. Bristogianni, F.A. Veer, R. Nijsse, 2020. The Application of Waste Float Glass, Recycled in Structural Beams made with the Glass Casting Method, Challenging Glass 7 Conference Proceedings, Ghent, Belgium.

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• F. Oikonomopoulou, T. Bristogianni, L. Barou, E. Jacobs, G. Frigo, F. Veer, R. Nijsse, 2018. Interlocking cast glass components, exploring a demountable dry-assembly structural glass system. Heron, 63 (1/2), p.103-138.

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• T. Bristogianni, F. Oikonomopoulou, C. Justino de Lima, F. Veer, R. Nijsse, 2018. Structural cast glass components manufactured from waste glass: Diverting everyday discarded glass from the landfill to the building industry.  Heron, 63 (1/2), p.57-102.

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• F. Oikonomopoulou, T. Bristogianni, L. Barou, F. Veer, R. Nijsse, 2018. The potential of cast glass in structural applications. Lessons learned from large-scale castings and state-of-the art load-bearing cast glass in architecture. Journal of Building Engineering, 20, p.213-234.

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• G. M. Anagni, T. Bristogianni, F. Oikonomopoulou, P. Rigone, E. S. Mazzucchelli, 2020. Recycled glass mixtures as cast glass components for structural applications towards sustainability, Challenging Glass 7 Conference Proceedings, Ghent, Belgium.

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• F. Oikonomopoulou, T. Bristogianni, L. Barou, F. Veer, 2019. Dry interlayers out of cast polyurethane rubber for interlocking cast glass structures: experimental exploration and validation. SEMC 2019 Proceedings, Cape Town, South Africa. 

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• T. Bristogianni, F. Oikonomopoulou, F. Veer, R. Nijsse, 2019. The effect of manufacturing flaws in the meso-structure of cast glass on the structural performance. SEMC 2019 Proceedings, Cape Town, South Africa.

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• F. Oikonomopoulou, T. Bristogianni, L. Barou, E. Jacobs, G. Frigo, F. Veer, R. Nijsse, 2018. A novel, demountable structural glass system out of dry-assembly, interlocking cast glass components. Challenging Glass 6 Conference Proceedings, Delft, The Netherlands, p.71-82.

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• T. Bristogianni, F. Oikonomopoulou, C. Justino de Lima, F. Veer, R. Nijsse, 2018. Cast Glass Components out of Recycled Glass: Potential and Limitations of Upgrading Waste to Load-bearing structures. Challenging Glass 6 Conference Proceedings, Delft, The Netherlands, p. 151-174.

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Invited Talks

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- Invited speakers at Burg Giebichenstein Kunsthochschule Halle, University of Art and Design, “on recycling glass waste through casting”,

F. Oikonomopoulou & T. Bristogianni , Leibzig, Germany, 2019

- Invited speakers at the Engineered Skins 2019 Symposium, Cambridge University, on “the potential of cast glass for structural applications”, F. Oikonomopoulou & T. Bristogianni, Cambridge, UK, 2019

- Invited speakers at Princeton University, on “the potential of cast glass for structural applications”,

F. Oikonomopoulou & T. Bristogianni , NJ USA 2019

- Invited speakers at Athens Design Lab, on “the potential of cast glass for structural applications”,

F. Oikonomopoulou & T. Bristogianni , Athens Greece 2019

- Invited speakers at AGC, on “the potential of cast glass for structural applications”  

F. Oikonomopoulou, T. Bristogianni, Belgium  2019

- Invited speakers at Walk & Talk session, Dutch Design Week :  “Re3 Glass: A novel design philosophy for load‐bearing structures out of waste glass”,

F. Oikonomopoulou & T. Bristogianni , Eindhoven 2018

- Invited speakers at Gevel Beurs 2018, organized by 4TU.Bouw: “Re^3 Glass”,

F. Oikonomopoulou & T. Bristogianni, Rotterdam 2018

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Exhibitions

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- Topics Media Station, Parlamentarium, Brussels: 2021 – ongoing

- Vitra Design Museum, Schaudeport Lab, Germany, 2019
- Exhibition of prototypes at the permanent material collection of the museum
- Hôtel Droog, Amsterdam, The Netherlands, 2018
- Dutch Design Week Exhibition, Eindhoven, The Netherlands, 2018 
- GlassTec Trade Fair, Dusseldorf, Germany, 2018
- 16th International Architecture Exhibition | La Biennale di Venezia 2018 
- Venice Design exhibition, Palazzo Mora, Venice, Italy, 2018
- Gevel 2018, Ahoy, Rotterdam, The Netherlands, 2018 
- Dig-it TU Delft Research Exhibition, Delft, The Netherlands.

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Awards

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- STARTS prize Nominee by Ars Electronica , 2020
- New Material Award Nominee, by Het Nieuwe Instituut, Fonds Kwadraat & Stichting Doen, 2018

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Grants

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4TU. Bouw Lighthouse granted project: “Re3 Glass” (50.000€), 2017

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Contact

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t.bristogianni@tudelft.nl
f.oikonomopoulou@tudelft.nl