A “Marshall plan” costing “tens of billions of Euros” is needed to bring the tens of thousands of bridges across Italy that have exceeded their design life up to standard, a leading Italian research body has demanded.
The call has been made in the wake of the collapse of the Polcevera viaduct by the largest public research institution in Italy, the National Research Council (NRC).
It cites a sequence of collapsing Italian road infrastructure that has become “a worrying regularity” for some years and highlights that age is the common factor, with most of the infrastructure in Italy built of reinforced concrete in the 1950s and 1960s. It adds that severe cost pressures following the Second World War meant that compromises were often made between capital cost and longevity of the structures.
“In practice, tens of thousands of bridges in Italy have exceeded, today, the life span for which they were designed and built,” said NRC director of the Institute of Construction Technology Antonio Occhiuzzi. “In many cases, the foreseeable costs for the extraordinary maintenance that would be necessary for these bridges exceed those associated with demolition and reconstruction.”
“The figures necessary for the modernisation of road bridges in Italy would be expressed in tens of billions of Euros,” he added. “In order to avoid tragedy such as that happened in Genoa, a sort of “Marshall plan” for Italian road infrastructures would be indispensable, based on the replacement of most Italian bridges with new structures characterised by a useful life of 100 years.”
Recent failures cited by the NRC include:
- The July 2014 collapse of a span of the Petrulla viaduct between Ravanusa and Licata, with the span breaking in half due to failure of the post-tensioning
- The October 2016 collapse of a flyover in Annone (Lecco) due to an exceptional load that was incompatible with the strength of the structure, which was below the original design capacity due to its age
- The March 2017 collapse of an overpass on the Adriatic motorway during maintenance work
- The April 2017 collapse of a span of the Tangenziale di Fossano (Cuneo), breaking in half in a similar way to the Petrulla viaduct
“Today part of the Morandi viaduct has collapsed, which will probably lead to complete demolition and replacement of the work,” said Occhiuzzi. “The element in common is the age of the structures: most of the Italian road infrastructures (road bridges) have exceeded 50 years of age, which correspond to the useful life associated with the reinforced concrete works made with the technologies available after World War II.”
Occhiuzzi stressed that the Polcevera viaduct, more commonly known as the Morandi bridge, owes its name to the “brilliant designer / executor of the work, one of the names that, together with Freyssinet (France), Leonhardt (Germany) and Maillart (Switzerland), changed the concept of bridges in Europe and in the world”.
Built between 1963 and 1967, Occhiuzzi described it as an example of “absolute rationalism” and rejected suggestions that it was badly designed.
He also said there was no immediate reason to doubt owner/operator Autostade’s maintenance regime, instead suggesting that more development was required in monitoring systems.
“It also appears that the Morandi viaduct was under continuous and constant observation, and there is no reason to doubt that the concessionaire has used all the technologies available today,” he said.
“The sudden collapse, therefore, suggests that the monitoring and surveillance systems adopted are not yet sufficiently evolved to ward off tragedies like this one this morning.”
Like what you’ve read? To receive New Civil Engineer’s daily and weekly newsletters click here.