Also Riccardo Morandi designer and author of the bridge who bears his name (wears), was convinced that something might not work out. So much so that in 1979, twenty years after the construction of the viaduct above the Ligurian city, he argued that it was necessary to intervene to reinforce it
"I think that sooner or later, and perhaps over a few years, it will be necessary to be treated for the all traces of rust to remove exposed reinforcements and then cover everything with elastomers with a very high chemical resistance, "Morandi said. For the engineer, the saltiness caused such damage to justify a "corrosion alarm."
Reporting the report signed by Morandi is La Verità. The report was entitled "The long-term behavior of viaducts subject to heavy traffic in an aggressive environment: the viaduct at Polcevera, in Genoa". "The structure – reads it – is attacked by the sea breeze (one kilometer long) that is channeled into the valley traversed by the viaduct, creating an atmosphere with high salt content that, in addition, on its way before it reaches the structure, it mixes with the vapors of the steel chimneys and is saturated with very harmful fumes. "
What caused the collapse in which 34 people were killed is not entirely clear yet. Perhaps the judiciary will identify causes and responsibilities. Those responsibilities that, for now, Autostrade per l & # 39; Italia does not intend to assume. But the signs of the problems that the viaduct would have had were all there. We still have to ask ourselves how it is possible that Autostrade, as explained yesterday by Giovanni Castellucci can say that "all relations we had showed us a good state of health", said Morandi, more than thirty years ago warned against the risk & # 39; s Corrosion
"The external surfaces of the constructions – explained the engineer – but especially those exposed to the sea and therefore more directly attacked by the acidic vapors of the chimneys, begin to show signs of aggression of chemical origin. exhibit ". So much so to mark a "loss of surface resistance of concrete ."
The first problems were discovered in some plates that were "literally corroded in just over five years" and "they had to be replaced, with rather complicated processes, with stainless steel elements." For Morandi, a way to protect the bridge was to use synthetic resins and elastomers to "increase their chemical and mechanical resistance to wear."