The human cost of the Genoa bridge collapse

Materials World magazine
24 Sep 2018

After part of the Morandi Bridge collapsed in Genoa, Italy, in August, leaving 43 dead, investigations into the cause reveal a split country. Ines Nastali reports.

One thing is clear in the aftermath of the deadly bridge collapse in Genoa, Italy – according to the city’s chief public prosecutor Francesco Cozzi, human error led to the fatal incident on 14 August, which saw 200m of the highway bridge collapse during a thunderstorm, causing cars and people to fall off the bridge and plunge around 100m down.

However, at the time of writing, it has not yet been determined which decisions made by human hand caused the death of more than 40 people who drove on the bridge, while it had been under structural surveillance and improvement work.

Accusations are flying from the public prosecution, to politicians – between the ruling coalition of the anti-establishment and right wing parties 5 Star Movement (M5S) and the League and the former government of the centre-left party Partito Democratico – as well as towards the private bridge and motorway operator Autostrade per l’Italia and the EU.

They are all trying to find an explanation as to why the bridge, built of reinforced concrete cable stays, was kept open, even though it was in need of repair and had been monitored for months. It is known that transport civil servants were warned about the structural weakness of the bridge piles in February 2018, months ahead of the incident, as a study into the status of the Morandi Bridge, named after its architect Riccardo Morandi, commissioned by the bridge operator had shown.

A story unfolds

Back in November 2017, the Polytechnic University of Milan, Italy, found a disparity on the bridge. ‘It is probable that the disparities are traceable to precursing stressors generated, for example, by corrosion in the stay-cables and injection defects,’ engineers and professors Carmelo Gentile and Antonello Ruccolo reported in the confidential report delivered to Autostrade and quoted by Italian newspaper La Stampa. They added that the bridge was only at 80% resistance capacity due to corrosion.

In the days after the collapse, a document from 2016 sent to the Italian Ministry of Infrastructure and Transport by the then Senator of the Liguria region Maurizio Rossi was leaked. It entails the latter’s concerns that traffic around the bridge in Genoa is totally congested and that, ‘recently, the bridge has been the subject of an investigation into a worrying failure of the joints, which has made extraordinary maintenance work necessary without which the risk of the bridge’s closure is high’.

This followed an earlier report from 2003, by the University of Genoa that said ‘the presence of marine aerosols and industrial gaseous pollutants’ has caused defects. And further back in the 1990s, ‘explorations with the endoscope highlighted the serious state of oxidation of the internal cables. Numerous strands and single fibres were severed or strongly oxidised, others were visibly released, suggesting a downstream breakdown,’ according to La Stampa. The reinforced concrete made inspection only possible with scanning equipment.

Local architect Diego Zoppi also voiced criticism, saying the fault lies in the initial construction materials. ‘The problem with the Morandi Bridge is that the tie rods were made of concrete and not metal. In the 1960s, they did not expect concrete to degrade and then collapse. 50 years ago, there was unlimited confidence in reinforced concrete. It was believed to be eternal,’ he told Italian news agency ANSA, adding, ‘With the continuous vibrations of traffic, the cement cracks let air pass through, which reaches the internal metal structure and making it oxidise.’

La favoletta

Not only were the materials used to build the bridge inadequate, but so was the planning of future use of the bridge, which was built in the 1960s and which has now developed into a vital transport connection between France and the port of Genoa.

Suggestions to divert traffic from it by building a bypass called La Gronda were opposed a few years ago – also by the now in government party M5S, with founder Beppe Grillo saying in a blogpost in 2013, the idea the bridge could collapse was a fairy tale.

The collapse therefore also shows insights into the split country that Italy is. While the League wants to invest in infrastructure to get the country’s economy going again by giving out contracts to local companies, M5S rose to popularity by opposing big construction projects such as La Gronda.

The mafia lead

With the political debate heating up, the collapse has also ignited claims that the Italian mafia might be involved by supplying sub-standard construction materials for the bridge back in the 1960s or for subsequent maintenance work. The local mafia’s core business is construction, claims University of Essex, UK, Criminology Lecturer Anna Sergi, who has done intensive research into mafia structures in Italy but also Canada and Australia over the past years. In an article in The Conversation, she writes, it is ‘a fact confirmed by anti-mafia prosecutors in one of the most recent investigations in the region, called Operation La Svolta, which ran from 2014-2016’.

While the cause of the collapse is still undetermined, at the time of writing, it looks as though a mix of failed attention and planning has led to the deterioration of the bridge. It will be seen if the local government manages to improve this in future. Speaking about the rebuild, for which a timeline has not yet been determined, Sergi said, ‘Given that the region of Liguria, and the city of Genoa itself, have already experienced the interference of mafia-run businesses in construction, there’s a high risk of mafia involvement in relief and reconstruction contracts in the aftermath of the Genoa bridge collapse’.

The island review

Meanwhile, the UK’s traffic authority, Highways England, issued a statement at the end of August ensuring the public that UK bridges are safe. ‘Highways England has a rigorous inspection regime for all structures, which takes into account design, age and likely maintenance needs. There are more than 21,000 structures on England’s network of motorways and major A-roads, none of which are of similar design to the one in Italy. A very small proportion of our structures are suspension or cable-stayed bridges but none of them are of similar construction to the one in Genoa.’