Cemento armato. Strutture per la conquista dell'Impero

On September 18, 1935 the modern Decameré-Nefasit carriage road was inaugurated in Eritrea, the first Italian colony. In fifteen days, Italy would occupy Ethiopia, and the road that had been designed to transport General De Bono’s troops from the port of Massawa to the Abyssinian plateau was officially opened to traffic just in time. 134 km and 8 imposing bridges that the Regime propaganda disguised as a generous endeavour to bring the great work of civilization overseas were built in just seven months thanks to exhausting schedules and reserved material supplies. The story began in the late 1934 when the Eritrean Government awarded the contract for the construction of the whole section of the new carriage road to Società Italiana Costruzioni e Lavori Pubblici (Italian Company for Building and Public Works). Hence, mass recruitment of workers began in Italy. On February 27, 1935 a group of 5,500 workers left for Eritrea. Two engineers, Guido Sassi and Attilio Arcangeli, both with great expertise in reinforced concrete construction, would be the directors of the contractor’s small technical office. In line with De Bono’s plan, they had only one month to propose the route and design a typical bridge whose construction could be commenced immediately by non-trained workers with the only use of ‘field’ means of work. In their position within the fascist hierarchy, the engineers turned that challenge into an opportunity to start a series of scientific and design experimentations on the structural behaviour of reinforced concrete. So they created a structure that would adjust to African warm climate and be able to resist the high loads of heavy artillery, gradually completed by the invention of handcrafted construction devices to contrast parasitic effects. An example was a peculiar ‘handcrafted semi-articulation’ patented by Sassi on March 16, 1935. Site work was very hard: concrete was cast exclusively overnight while during the day reinforcements were covered with wet sacks to extract heat. On October 28, 1935 even the last and most imposing structure of the carriage road was completed: the Dogali River Bridge that troops had already crossed on October 2 when formworks were still in situ. At the war’s height, the army was by then fully deployed. According to the military plan, road construction works had to be speeded up to support the troops’ advance. However, at the same time as the opening of the new building sites, the invasion was condemned, and economic sanctions were imposed against Italy. As a result, a strict policy of autarchy began. So the logistical difficulties in building the Decameré- Nefasit road were superimposed by an actual restriction on iron use. Captain Sassi, ‘first of all by the Duce's order’, ventured into the design of a new autarchic structure that could be made with non-reinforced concrete. The African adventure, as part of an insane utopian dream, remains testify to a creative experimental exercise that, within autarchic building, characterized the original use of reinforced concrete for war purposes and the colonial declination of the design of structures.