Prefabricated lightweight construction with post-tensioning: A conceptual design prototype of 3D-printed polymer slab system

The confluence of structural optimization and additive manufacturing (AM) has significantly expanded the design space of architectural tectonics. This research explores the integration of architectural tectonics and rationalization in prefabricated lightweight construction, focusing on the conceptual exploration of a 3D-printed floor slab prototype. The lightweight slab system is designed for temporary construction for the adaptive reuse of industrial buildings. Leveraging large-scale fused granulate fabrication (FGF), the study aims to bridge bespoke fabrication processes with architectural form-finding methods. The floor slab system is divided into prefabricated modules that are assembled with post-tensioning steel cables. Structural optimization and toolpath planning were employed to enhance material efficiency and structural integrity, thereby making the slab system lightweight yet strong. This research adopts a structural design strategy by slicing the floor slab, conceptualized as a folded-plate system, into multiple cross-sections that correspond to 3D-printing layers. Manufacturing constraints are translated into bespoke tectonics through toolpath planning. Prototyping experiments were carried out using transparent Polycyclohexylenedimethylene terephthalate glycol (PCTG) to expose the material distribution inside modules, manifesting the design principle of “form follows performance”. The optimized geometry and constraint-driven tectonics indicate that rationalization for efficiency could be integrated with appealing tectonics in digital fabrication.