Fornix: the circular platform-frame.

This paper explores the potential contribution of stone construction methods to environmental sustainability and modern construction and structural requirements. Drawing inspiration from an unrealized project by architect Pino Pizzigoni (Bergamo, 1944), it examines the spatial equilibrium of interlocking stone modular ribs designed without binders or reinforcement materials. The study addresses the structural performance, customization possibilities, and constructability of these structures by employing an integrated concept development method that combines a parametric design setting with mechanical analysis and physical concept models. The conceptual study indicates that the interlocking ashlars shall be able to maintain the thrust line within the structural section, allowing the structure to absorb external stresses typical in building constructions. Moreover, it suggests the possibility to achieve a three-dimensional equilibrium of mutually self-supporting rigid bodies that are firm even during installation. The findings lay the groundwork for a computational design method to produce resistant, spatially coherent ribs composed of modular elements that self-balance during construction and achieve improved structural capacity under operational conditions.