Architecture as a challenge

The first major international retrospective on the work of Italian engineer Pier Luigi Nervi, Architettura come sfida ["Architecture as a challenge"] is an itinerant, research-based exhibition by an academic committee led by Carlo Olmo. Currently in the Fruttiere of Palazzo Te, Mantua through 25 November, it is organised by the Centro Internazionale d'Arte e di Cultura and, for this venue, has adopted the subtitle L'Industria e la Fabbrica Sospesa ["Industry and the suspended factory"].

The exhibition showcases twelve works by Nervi highlighting major stages in the research and triumph of the architectural inventive of one of the most internationally acclaimed Italian engineers, who often rose above indifference and sterile local debate.

The visitor route commences with the little-known Augusteo film-theatre in Naples, designed between 1924 and 1929, with input from architect Arnaldo Foschini. This cinema was very dear to the 35-year-old Nervi as it featured his first experiments on hyperstatic frame structures in reinforced concrete. It was, however, in 1932 that he acquired international renown, with the Berta municipal stadium in Florence, published in Quadrante and Architettura and embraced by Rationalism as a synthesis of structural and aesthetic intervention. The materials on show illustrate all the tortured design and construction options produced and the addition of the raised stands in the early 1950s. Engineering-research imagery of the times, however, centred on the reticular vaulted roofs of the Orbetello, Orvieto and Torre del Lago aircraft hangars, immortalised in photographs by Studio Vasari and presented in a Ponti editorial in Domus as "Stile delle strutture" ["structural style"]. Proposed by Nervi & Bartoli to the Italian air force, they were developed from tests conducted on small-scale models by Guido Oberti at Milan Polytechnic. Their final construction preceded the concept of the prefabricated structures widely adopted after the war.

The post-war recovery was highlighted by the construction of a Hall in Turin's Palazzo delle Esposizioni, in which the use of prefabrication accompanied Nervi's invention of "ferrocement", which reinforced thin slabs with wire mesh and pieces of steel bars. Then came an international partnership for UNESCO's Paris headquarters, opposite the Tour Eiffel, with Marcel Breuer and Bernard Zehrfuss under the supervision of a formidable CIAM group comprising Costa, Gropius, Le Corbusier, Rogers and Markelius. When designing the Assembly Hall, Nervi placed all the sculptural potential of concrete at the service of the project's required impact.

The Palazzetto dello Sport, built with Annibale Vitellozzi in 1957, became the iconic architectural backdrop to the Rome Olympics, held three years later. Only understood at the time by Bruno Zevi, its roof had a 60-metre diameter based on the basic concept of on-site prefabrication, which had already been tested with the hangars before the war. Built to mark the centenary of Italian Unification, the Palazzo del Lavoro in Valentino Park, Turin was constructed in just a few months, bringing together concrete structures with differently shaped pillars and steel — the "ribs" of the 16 umbrellas with 40-metre sides that, combined, cover the span of an extraordinary celebration of national production, with interiors by Gio Ponti.

The Stock Exchange Tower in Montreal, designed with Luigi Moretti for the Società Generale Immobiliare between 1961 and 1965, and St Mary's Cathedral in San Francisco, with Pietro Belluschi (1963-71), reiterated the importance of the structure in a building's architectural image but, more than all other Nervi spaces, the contemporary "Sala Nervi", with its structural inversion of the traditional roof, is forged in the collective memory of audiences presided over by the weary figures of recent Popes.

The exhibition ends, after the Risorgimento bridge in Verona, with the construction of the Italian Embassy in Brasília, designed with his son Antonio for the new capital in the early 1970s, shortly before both passed away within a brief space of time.

These twelve works, illustrated in drawings, models, construction-site and news photographs, act as a frame to the design of the Cartiera Burgo [Burgo paper factory] in Mantua, which is the focal point of the exhibition in Palazzo Te, produced by Cristiana Chiorino and backed by the Gruppo Burgo. The recent rediscovery of some formworks used to cast the paper mill's isostatic slab has further exposed aspects of Nervi's research into this construction and, in the exhibition, they offer the chance to compare the design illustrated on paper with the actual construction.

This work still blends discreetly and cleverly with the natural design of the city's lakes and seems not only to convey a technical idea but also a sense of the essence of architecture, portrayed by Nervi in a section that shows the two sides of the "suspended factory", with a poplar trunk entering and a roll of paper emerging at the other side.

Promoted by the Comune di Mantova and the Museo Civico di Palazzo Te, the exhibition is sponsored by the Regione Lombardia and the Polo Territoriale di Mantova of Milan Polytechnic. Luigi Spinelli