Fabrication methods for topology-optimized massive glass structures

Recent research at TU Delft has highlighted the potential of using structural Topology Optimization (TO) for designing large monolithic cast glass structures of maximized stiffness with minimal mass. The mass efficiency of these structures results in considerably shorter annealing times and, consequently in improved manufacturability in terms of time, energy and cost efficiency. Nonetheless, the geometrical complexity and customization of the resulting forms renders them challenging in terms of fabrication. Exploring the manufacturability of such intricate glass structures, in this paper we discuss the different possible fabrication methods for three-dimensional glass structures of complex and customized geometries, via a review of existing literature, experimental work and prototyping. Specifically, with the aim of addressing all possible manufacturing solutions, we look into the following fabrication methods: (i) casting in disposable moulds; (ii) waterjet cutting and lamination of float glass panes and; (iii) additive manufacturing of glass. We assess these methods based on a set of criteria linked to the structural performance, visual quality, fabrication limitations and sustainability. Accordingly, we discuss the potential, challenges and practical limitations of each fabrication method for real-world applications of TO glass structures. Subsequently, we propose the integration of alternative constraints into the TO formulation, so that customized TO tools that better reflect each fabrication method can be created.