Stone 3D Printing
The demonstrator for Marmomac 2025 is the combination of structural optimization, advanced 3D printing and knowledge derived from the ancient stone masons of the great Gothic cathedrals.
Demonstrator at Marmomac
The exhibit showcases a 2 m × 2 m funicular floor assembled from binder‑jetted tiles. Each element is printed without support from waste quarry material and transported to site where it can be assembled.
The 13 structural tiles that make up the geometry are dry-assembled on-site. Removing the need for mortars, glues or mechanical connections allows disassembly, replacement of individual elements, and reuse in different configurations.
Structural principle
A funicular floor is a thin structural element whose geometry is shaped so that loads are carried primarily in compression, minimizing bending and material use. The form follows the inverted thrust line, guiding forces efficiently to the supports.
Because the load path is dominated by compression, less material is required to achieve stiffness and strength, lowering mass and embodied carbon while maintaining performance.
Tension at the edges is managed by perimeter ties or by locally thickening the shell at the supports, keeping the system primarily in compression.
The floor exposed at Marmomac 2025 is a scaled version of what is possible to achieve in real construction. Such floors are commercialized by VAULTED AG, an ETH Spin-off generated from the Block Research Group.
Our Journey
The demonstrator exposed at Marmomac is the latest of a series of prototypes that allowed us to develop the technology even further.
The first large scale application of the Geo-BJT technology in a funicular floor is the Arzo prototype. In this occasion, we also proved the transportable micro-factory concept, by installing the 3D-printer in a standard container and transporting it directly to the quarry.
In the beginning of 2025 we refined the concept and reduced the complexity of both printing and assembling the structural element. The result is a beautiful white marble funicular floor 1.2 × 1.6 m in plan.
Ready to continue?
Learn more about the people behind this project or get in touch with us to explore collaborations.