Experimental Durability Analysis of Historical Ferrocement

The paper presents the results of a recent testing campaign carried out on the ferrocement elements built by Pier Luigi Nervi in the structures of Torino Esposizioni. These pavilions, built between 1947–1953, allowed Nervi to apply for the first time in a large structure his advances in the use of ferrocement in civil construction that he had pioneered during the war. The results obtained by Nervi were patented immediately after the end of the construction site and would have characterized Nervi’s technique for his whole career. Before Nervi’s civil applications, ferrocement was mainly used to build boats. The material is characterized by the multiple layers of mesh or fine rods completely impregnated with cement mortar, which Nervi noted could be applied to build slabs and roofing elements by using a very low amount of material. Considering the historical value of the structures and since the ferrocement elements are extremely thin, to investigate the durability of this material, small-scale ferrocement mockups were built in the laboratory, starting from a small sample collected on-site. A detailed testing program was developed, which included applying different treatments to the specimens before subjecting the samples to an accelerated weathering procedure to test the effects of each (mixed-in corrosion inhibitor, surface-applied inhibitor, etc.). The analysis of the ferrocement developed by Nervi in his constructions is a mandatory step for evaluating the health state of these elements and will help define the guidelines for their conservation. Moreover, it will help to expand the knowledge of Nervi’s system.