Turin Exhibition Palace

Originally published in Domus 231/December 1948

Architect Biscaretti Ruffia added a complex of halls and rooms to the part of Turin's Palace of Fashion—designed by the architect Sottsass [ed note: Ettore Sottsass Sr., father of the Memphis designer]—that had been damaged in the war. The complex will house various exhibitions, the first of which will be the Motor Show. A precast structure designed by the engineer Pierluigi Nervi was utilized for the construction of the large central hall. With an almost square plan, two side galleries and a semicircular apse, the hall covers approximately 200 square meters. The heavier structures, which could not be placed in the upper zone, are located in another semi-circular hall below it. Nervi, designer of the precast concrete structure, pointed out how the limited amount of time allotted for construction and the unusual size of the building created a series of uncommon construction problems that are difficult to resolve through the use of traditional building systems. He employed new construction procedures that had already been successfully utilized by the engineering firm Nervi and Bartoli of Rome.

These systems are essentially based on prefabrication and the use of ferrocement. The large 96m X 75m hall has a thin, corrugated vaulted roof made of a series of ferrocement components structurally bound to each other. The installation took place by using a special scaffolding with reinforced concrete ribs along the ridges and valleys of the roof section. The elements, as wide as one of the "waves" and 4.40 meters in length, have a thickness of 4 centimeters.

The average thickness of the entire vault is less than 8 centimeters. The great importance of this particular lightness—which made it possible to cover large spans using limited material with incredible ease and construction speed—is evident.

The advantages of the construction process are combined with successful architectural expression. To be noted in this regard are the fan-shaped transitional elements connecting the corrugated roof to the structural piers. For the rotunda's half-dome, having a diameter of 40 meters, the construction system utilized was based on the prefabrication of rhomboid-shaped elements, connected by ribs in reinforced concrete. The structure is completed on its upper surface by a ferrocement slab having a thickness of approximately 3 centimeters. The overall depth, taking into account the dimension of the ribs, is approximately 7 centimeters.

The ribs connecting the precast rhomboids are visible on the interior and constitute an effective architectural motif. The roof slabs over the lower level and the side galleries of the hall are replaced by precast beams 7.50 meters in length, supporting slabs with a double curvature; these are bound together and statically completed by a thin floor slab.

The prefabrication process made the shape of the beams possible, with their enlargement towards the structural piers responding integrally to the building's static requirements.

Indeed it can be noted that the spontaneous architectural expression, derived from the sincere exhibition of static and constructive forms, is the main feature of all the structural elements in the Turin Exhibition Hall.