Bridge cable damaged months ago but no action taken, Italian media report
Reported reduction in strength of 20% wasn't deemed significant enough to limit traffic
Engineering experts determined in February that corrosion of the metal cables supporting the Genoa highway bridge had reduced the bridge's strength by 20 per cent — a finding that came months before it collapsed last week, an Italian newsmagazine reported Monday.
Despite the findings, Espresso wrote that "neither the ministry, nor the highway company, ever considered it necessary to limit traffic, divert heavy trucks, reduce the roadway from two to one lanes or reduce the speed" of vehicles on the key artery for the northern port city.
A large section of the Morandi Bridge collapsed Aug. 14 during a heavy downpour, killing 43 people and forcing the evacuation of more than 600 people living in apartment buildings beneath another section of the bridge.
Prosecutors are focusing their investigation into the cause of the bridge's collapse on possible faulty maintenance or design flaws but have not identified any targets.
After workers heard creaking noises coming from the part of the bridge that was still standing, firefighters suspended an operation to allow evacuated residents to retrieve their belongings from apartments under the bridge.
The Italian news agency ANSA reported that officials have ruled out that the sound could be caused by wind, and that more checks are underway.
Firefighters on the ground confirmed the reports but declined to be identified as they were not authorized to speak to the media. Work continued to clear the tons of bridge debris that cascaded onto a dry riverbed below.
The Morandi Bridge was a key artery that linked highways to Milan and France, a vital lifeline for both commercial traffic as well as vacationers bound for the mountains and Mediterranean beaches.
In its report, Espresso cited the minutes of a meeting of the Genoa public works superintendent, which included Roberto Ferrazza, an architect named to head a government commission looking into the disaster, and Antonio Brencich, an engineer who has been outspoken about the bridge's flaws.
Espresso reporter Fabrizio Gatti told SKY TG24 that a reduction of 20 per cent strength would not be significant in a modern bridge, but on a structure with the known defects of the Morandi Bridge it should have merited swifter, more decisive action.
"Everyone was well aware of the situation on that bridge," Gatti said.
Graziano Delrio, the transport minister at the time, told a news conference Monday that "no one ever signalled the necessity of limiting traffic" on the bridge.
Morandi emphasized need for upkeep
Ricardo Morandi himself warned four decades ago that it would require constant maintenance to remove rust given the effects of corrosion from sea air and pollution on the concrete, Italy's public broadcaster reported on Sunday.
RAI broadcast excerpts of the report Morandi penned in 1979, 12 years after the bridge bearing his name was inaugurated in Genoa. The Associated Press downloaded the English-language report from an engineering news portal.
At the time of writing, Morandi said there was already a "well-known loss of superficial chemical resistance of the concrete" because of sea air and pollution from a nearby steel plant. He said he chose to write about it because the degradation represented a particular "perplexity" given the "aggressivity" of the corrosion that wasn't seen in similar structures in different environments.
Morandi, who died in 1989, reaffirmed the soundness of the reinforced concrete bridge design he used but warned: "Sooner or later, maybe in a few years, it will be necessary to resort to a treatment consisting of the removal of all traces of rust on the exposure of the reinforcements, to fill in the patches."
He recommended using an epoxy resin to cover the reinforcements with materials "of a very high chemical resistance."
Government appears divided
Bidding on a 20-million-euro ($29.9 million Cdn) contract to reinforce two of the major supports for the bridge, including one that collapsed, was scheduled to close next month.
The Italian government, meanwhile, appeared divided on how to proceed in relation to Autostrade per l'Italia, the company that operated the section of highway that collapsed.
Transport and Infrastructure Minister Danilo Toninelli was quoted by the Milan daily Corriere della Sera as saying that he supported the nationalization of Italy's toll highways, including the bridge.
"Think of all the revenues that would return to the government through tolls, to use not to donate to shareholders' dividends but to reinforce the quality of service and security on our roadways," Toninelli was quoted as saying.
But deputy premier Matteo Salvini, who is also Italy's interior minister, told reporters he remains in favour of public-private cooperation in infrastructure.
Owner's shares fall 9.5%
Premier Giuseppe Conte says procedures have begun to revoke Autostrade per l'Italia's concession to operate some 3,000 kilometres of Italian highways, about half of the total highways operated by private companies.
Italy's main union confederation estimates it would cost Italy between 15 billion and 18 billion euros ($22.4 billion Cdn to $30.8 billion Cdn) to revoke the highway rights.
The company that owns Autostrade, Atlantia, lost 9.5 per cent in its shares to 17.50 euros in trading Monday, after a late opening due to volatility. It shed 22 per cent last Thursday, the first trading day after the government announced its intentions, before returning to positive gains on Friday.