Original name
Torino Esposizioni Salone B e C [Torino Exhibition Hall B and C]
Original use
Exhibitions/pavillion
Current use
Exhibitions/pavillion
Engineers
Roberto Biscaretti di Ruffia, Pier Luigi Nervi
Concrete by reinforcement
Concrete is a relatively brittle material that is strong in compression but less so in tension.
To increase its overall strength, steel rods, wires, mesh or cables may be embedded in concrete before it sets. This reinforcement, often known as rebar, resists tensile forces. By forming a strong bond, the two materials are able to resist a variety of applied forces, effectively acting as a single structural element .
A composite structural material comprising thin sections consisting of cement mortar reinforced by several closely spaced layers of steel wire mesh.
Ferrocement is a low self-weight, highly versatile form of reinforced concrete.
It consists of cement mortar and a large amount of small-diameter wire mesh embedded uniformly throughout the cross section. The strength depends on two factors: the quality of the sand/cement mortar mix and the quantity of reinforcing materials used.
Construction method
In this case, the concrete can be made by mixing the components directly on site, or it may be transported from a production plant in concrete-mixer trucks.
This method has the disadvantage of leaving the concrete exposed to the elements while it is setting. Whereas, with other methods, the environmental conditions can be controlled during setting, providing greater control over the outcome, with cast-in-place concrete a series of tests and protocols are necessary to verify its final strength.
PRECAST ON SITE:
In larger and more complex construction projects, a concrete production plant may be installed on the construction site or nearby. The precast elements are moved into place once they have reached their maximum strength. This reduces transportation costs and ensures the concrete will set in the same environmental conditions as the building site. This may be more necessary with structures that combine cast-in-place concrete with prefabricated elements.
PRECAST IN FACTORY, WORKSHOP:
Any concrete element can be manufactured ahead of time and transported to the site once it has set. In this case, the control over geometry, appearance, finish and strength can be as strict as necessary. It can also be ensured that the pieces will be exactly identical to one another.
Prefabricated elements can be of any type: from façade panels and pavements to decorative elements (such as cornices or capitals) and structural elements (columns, slabs, beams, etc.).
These elements may be part of a commercial catalog or specially designed for a specific project. A series of pieces may also be sold as a coordinated and interconnected system to build a complete structure or even an entire building.
Voussoirs are the pieces that join together to form an arch. In the context of reinforced concrete structures, this idea also holds true for linear structures (beams, girders) that are built by adding small pieces that fit together, like vertebrae in a spinal column. The pieces used in these structures are prefabricated, and they are specifically designed to form a system.
The Spanish architect Miguel Fisac can be considered a master of this type of structure
Architectural concrete
- textured walls
- wooden formwork finish
- stamped concrete
- exposed aggregate concrete, colored concrete, etc.
Structural types
It is an archetypal form and one of the oldest forms in architecture, dating all the way back to prehistoric times. It is characterized by being subject only to compression loads, although it produces outward thrusts that need to be absorbed either through volume or geometric strategies (such as buttresses or flying buttresses). It is a typical structure used in tunnels.
The shape of the structure as a whole usually coincides with that of the building, as in the case of vaults or domes, for example.
Felix Candela and Pier Luigi Nervi both made exemplary use of this type of structure.
State of Conservation
Description
The engineer Pier Luigi Nervi was a key figure in the development of concrete construction technology in the 20th century. He combined brilliance as a structural engineer with extraordinary creativity and an ability to create beautiful structures, while exploring new aesthetic frontiers and techniques in the use of concrete.
The Turin exhibition hall is a rectangular space, 75 meters wide by 96 long, with an apse at one end. One of the premises for the design was that the building needed to be completed in a very short span of time, just eight months. The structure that Nervi devised is based on prefabricated elements: it is made up of ferrocement voussoirs that are assembled on site, which form a parabolic section that covers the entire width of the building. The thickness of the concrete pieces, with a carefully studied design, ranges from 4 cm to 8 cm, and they incorporate windows to let in light from the side, making the roof into an immense lattice. The rigidity of the whole is generated by the corrugated or waved section of the roof, which is created by joining together the prefabricated elements with the ribs, cast in situ, which are situated at the crests and troughs of each wave. At its base, the ribs are connected in groups of four to pillars, which are inclined according to the direction of the loads. This makes the structure permeable as it comes into contact with the ground, creating an additional structure on each side with loft spaces, which serve as auxiliary spaces for the central exhibition area.
The structure of the apse – a semi-dome with the form of a spherical cap – is also unique and of great interest: it was built using a system of prefabricated concrete panels, in a rhomboid shape, with a system of interconnecting ribs between them. This system is similar to what Nervi used, 10 years later, for the Palazetto dello Sport in Rome.
Italy
Corso Massimo d'Azeglio 15
Piamonte 10126 Torino
Commission
1947
Completion
1953