From Gaudí to NASA: The Sagrada Familia, a 19th-century project developed in the 21st century

The Sagrada Familia is the definitive case study of the chronological confluence: a design born from the ruled geometry of the nineteenth century that has only been completed thanks to aerospace technology and artificial intelligence of the twenty-first century. The shift from hand-carved stone to parametric architecture has transformed the temple into an architectural “software factory.” The technological leap that goes from Gaudí to NASA is due to the fact that Gaudí did not leave detailed plans, but plaster models and a geometric logic based on paraboloids, hyperboloids and conoids. To reconstruct their ideas, the technical office uses software such as Rhinoceros and Grasshopper, allowing complex shapes to be converted into accurate mathematical data. Fluid and stress simulation programs (similar to those used in aircraft design) have been applied to ensure the stability of large towers, such as the Virgin Mary or Jesus Christ. On the other hand, the “Supply Chain” of Faith appears with the exponent of an unimaginable Off-site Construction: Stretched Stone Panels that no longer refer us to the towers built stone by stone. Pre-assembled panels are manufactured in an external workshop (in Galera). These modules include the prestressed steel and stone, and are placed in the temple like pieces of a giant LEGO. And this is accompanied by Just-in-Time logistics: due to the lack of space in the centre of Barcelona, the supply of the modules is digitally coordinated so that they arrive and are hoisted immediately, minimising the urban impact. Although it is a historic building, its completion must dialogue with the new demands of sustainability: materials of the 21st century (they use high-strength stainless steels (Duplex) to guarantee a durability of more than 200 years in a marine environment, complying with the most demanding structural safety standards). And in addition, its Digital Twin has a BIM (Building Information Modeling) model that manages not only construction, but also predictive maintenance and the flow of millions of visitors. The Sagrada Familia is, in essence, a large-scale modular construction project. Its biggest challenge today is to integrate the Gloria (the missing main façade) into a consolidated urban fabric, a conflict that requires unprecedented Supply Chain and administrative management. How do post-tensioned stone panels work? What is the role of 3D printing in the reconstruction of Gaudí’s original models? We open the debate on the ethics of restoration in the face of new creation.