Foamwork: Challenges and strategies in using mineral foam 3D printing for a lightweight composite concrete slab

This paper presents an innovative design and fabrication workflow for a lightweight composite slab prototype that combines mineral foam 3D printing (F3DP) and concrete casting. Non-standardized concrete elements that are geometrically optimized for resource efficiency often result in complex shapes that are difficult to manufacture. This paper extends the research in earlier studies, showing that F3DP can address this challenge. F3DP is used to construct 24 stay-in-place formwork elements for a lightweight, resource-efficient ribbed concrete element with a 2 × 1.3 m footprint. This advancement highlights the improved robotic F3DP setup, computational design techniques for geometry and print path generation, and strategies to achieve near-net-shape fabrication. The resulting prototype shows how complex geometries that were previously cost-prohibitive can be produced efficiently. Discussing the findings, challenges, and future improvements offers useful perspectives and supports the development of this resourceful and sustainable construction technique.