> Exploring the shaping potential of cast glass in structures
using Topological Optimization & 3-D printed sand moulds
Cast glass, Structural glass, Topological optimization, Glass fabrication, 3-d printed moulds, 3d printing, Glass components.
2019 - ongoing
Dr. ir. Faidra Oikonomopoulou
Dr. ir. Faidra Oikonomopoulou
Dr. ir. Telesilla Bristogianni
TU Delft, AI Labs: C. Andriotis
MIT, Department of Civil and Environmental Engineering: J. Jewett, J. Voigt Carstensen
TU Delft Students: I. Bhatia, W. Damen, I. Stefanaki, D. Naous, D. Koopman, A. M. Koniari
In theory, glass casting enables the production of monolithic glass components of virtually any shape and cross-section. Such a vast forming potential, combined with the high compressive strength of glass offers endless possibilities in the design of diaphanous, monolithic structural glass members.
However, in practice, the shaping potential of cast glass in the built environment remains largely an unmapped field. The few realized examples of self-supporting structures comprising cast glass components, employ identical solid glass units of a simple shape and, roughly, up to 10 kg in mass. There are two main reasons behind these design choices for the solid glass units that are also, to an extent, intertwined: (a) the lengthy and perplexed annealing time required for cast glass elements of bigger mass and thickness and (b) the cost barriers imposed by shapes requiring complex high-precision steel or graphite moulds, or by a customized production.
Aim of this research is the design of massive structural cast glass components with the aid of topological optimization (TO) and 3D printed sand moulds.
By employing smart geometry / topological optimization (TO) we can reduce the mass to the one necessary, while maintaining high stiffness. A substantially lighter structure can greatly decrease the annealing time, enabling the fabrication of larger components in a significantly reduced time.
Such optimized and customized geometries require, in turn, complex, high-precision moulds. These, in sequence, result in higher fabrication costs that can jeopardize the marketability of the cast object. In this direction, 3D-printed sand moulds can be used for achieving customized, yet economic moulds for such customized components. 3D-printed sand moulds can provide a high-accuracy, cost-effective solution for solid glass components of complex geometry and/or of customized design. Although this mould technique is already used for metal castings, it remains still unexplored in the field of glass casting.
This research has been conducted primarily through MSc theses on both of the above aspects: Case-studies for the implementation of topological optimization in cast glass include the design of structural glass nodes (W. Damen), glass slabs (I. Stefanaki), domes (D. Naous) and pedestrian bridges (D. Koopman). Exploring a cost-efficient and high-accuracy fabrication method for such complex-in-shape components, student I. Bhatia conducted experiments on the use of 3D printed sand moulds for glass castings, focusing on the binder systems and surface finishes and on the kiln-casting of the desired geometries.
The results of this research highlight the great potential of 3D printed sand moulds as a cost-effective, high precision manufacturing method for customized cast objects of perplexed geometry, and the use of topological optimization for considerably reducing the raw material and cooling time needed for massive cast glass components.
MISTI Global Seeds Fund | MIT-Netherlands Lockheed Martin Seed Fund: “Unlocking the Potential of Cast Glass Structures through Additive Design” (2022-2024).
Material sponsorship by ExOne, 3Dealize and Hüttenes-Albertus.
W. Damen, F. Oikonomopoulou, T. Bristogianni, M. Turrin, 2022. Topologically optimized cast glass: A new design approach for loadbearing monolithic glass components of reduced annealing time. Glass Structures & Engineering, 7, p. 267–291 (2022), https://doi.org/10.1007/s40940-022-00181-1
F. Oikonomopoulou, A. M. Koniari, W. Damen, D. Koopman, I. M. Stefanaki, T. Bristogianni, 2022. Topologically optimized structural glass megaliths: Potential, challenges and guidelines for stretching the mass limits of structural cast glass. Proceedings of the 8th International Conference on Structural Engineering, Mechanics and Computation, Cape Town, South Africa.
F. Oikonomopoulou, I. S. Bhatia, W. Damen, F. van der Weijst, T. Bristogianni, 2020. Rethinking the Cast Glass Mould. Novel Techniques for complex and customized geometries, Challenging Glass 7 Conference Proceedings, Ghent, Belgium.
MSc thesis projects
A.M. Koniari, Just Glass: Development of a Topology Optimization Algorithm for a Mass-Optimized Cast Glass Component. MSc Thesis, TU Delft, 2022.
D. Koopman, The Topology Optimised Glass Bridge. MSc Thesis, TU Delft, 2021.
D. Naous, Topologically Optimised Cast Glass Shell: Topological optimisation and new fabrication methods for compressive free-form glass structures, MSc Thesis, TU Delft, 2020.
M. I. Stefanaki, Glass Giants: Mass-optimized massive cast glass slab, MSc Thesis, TU Delft, 2020.
I. Bhatia, Shaping transparent sand in sand: Fabricating topologically optimised cast glass column using sand moulds, MSc Thesis, TU Delft, 2019.
W. Damen, Topologically Optimised Cast Glass Grid Shell Nodes: Exploring Topology Optimisation as a design tool for Structural Cast Glass elements with reduced annealing time, MSc Thesis, TU Delft, 2019.