Rescuers are continuing to search for survivors of a bridge that collapsed in Genoa, Italy, killing at least 39 people and injuring 16 more.
The 50-year-old bridge collapsed during torrential rain on Tuesday, sending dozens of vehicles crashing onto a riverbed, a railway and two warehouses.
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Although it is too early to say what might have caused the tragedy, some officials say ongoing maintenance and rollback of infrastructure costs in Italy could have played a part.
Here’s what we know about the bridge and what experts say may have gone wrong:
What we know about the Morandi Bridge
The 1.2 kilometre-long bridge was built in the 1960s and designed by Riccardo Morandi with the intention to last 100 years. It is supported by two A-frame towers using concrete-encased stay cables.
The bridge carries a major road, the A10 motorway, which links northern Italy to France.
Some major repairs were done on the bridge in the 1990s and restructuring work was also completed in 2016.
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The bridge was flagged to be replaced
In 2016, an Italian engineering website published a critical analysis of the bridge.
Antonio Brencich, a professor specializing in reinforced concrete construction at the University of Genoa, called the span “a failure of engineering” in the 2016 interview.
“That bridge is wrong. Sooner or later it will have to be replaced,” Brenchic said.
Since the first decades of the bridge’s construction, repairs having to do with cracking and degradation of the concrete had to be done several times, he said.
Brencich added that it may have been more economical to rebuild the bridge because of the ongoing maintenance costs.
“I do not know when. But there will be a time when the cost of maintenance will be higher than a replacement,” he said, according to the Guardian.
Officials have stated that the bridge was properly maintained.
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So what went wrong?
It’s still too early to say what caused the bridge to collapse as the investigation is ongoing. But several explanations have been offered, such as the bridge’s condition and its ability to sustain a large increase in weight of traffic over the years.
According to the BBC, the bridge deals with heavy traffic — about 25 million vehicles every year — which may have sped up the deterioration of the structure.
Ian Firth, a former president of the Institution of Structural Engineers and a specialist in bridges, told the Guardian that the corrosion of the tendons or reinforcements may have been a factor.
“In addition, ongoing work on the bridge may or may not be partly responsible for the collapse,” Firth said. He added that the bridge featured a “very unusual design.”
Italy has also dropped its investment in infrastructure, especially compared to other European countries, the BBC reported.
Deputy Prime Minister and Interior Minister Matteo Salvini said the disaster showed that Italy needed to spend more on infrastructure.
“We should ask ourselves whether respecting these limits is more important than the safety of Italian citizens,” he said. “Obviously for me, it is not.”
He also said the private sector manager of the bridge had earned “billions” from tolls but “did not spend the money they were supposed to” and its concession should be revoked.
On Wednesday, the company that operates the bridge, Autostrade, said it had done regular, sophisticated checks on the structure before the disaster, relying on “companies and institutions which are world leaders in testing and inspections” and that these had provided reassuring results.
“These outcomes have formed the basis for maintenance work approved by the Transport Ministry in accordance with the law and the terms of the concession agreement,” it said.
— With files from Reuters