PrintNervi – Design and Construction of a Ribbed Floor System in the Digital Era

Ribbed floor systems, which include ribbed slabs and columns, are used extensively to enhance the structural performance of buildings. With the emerging topology optimization and advanced manufacturing techniques, the material usage and construction process of the ribbed floor systems can be improved significantly to achieve higher efficiency and sustainability. This paper presents a digital design and construction process for ribbed floor systems that combines a modified topology optimization method for ribbed slab design with a hybrid digital fabrication process for large-scale concrete casting. This new approach is tested through digital design and physical realization of a large-scale ribbed floor unit as proof of concept. The topologically optimized result and the constructed unit are compared with a famous historical floor system designed by Pier Luigi Nervi. The paper shows that the proposed design method, based on the bi-directional evolutionary structural optimization framework, can generate a slab design with a continuous rib layout and with higher structural stiffness. The paper also demonstrates that 3D printing of formworks for casting ribbed slabs and complex-shaped columns is feasible and sustainable. The new process presented in this paper can be used to design and construct a wide range of structures while minimizing material usage and labor cost.