Everything Needs Maintenance – The Morandi Bridge Collapse

Morandi Bridge, Genoa, ItalyEverything Needs Maintenance. What caused the Genoa bridge collapse – and the end of an Italian national myth? The image is of the bridge, before the collapse. (Click the image, for a larger view, and background info. Image by Davide Papalini)

Construction was from 1963 through 1967. It collapsed on August 14th, 2018.

43 people died. 600 people were made homeless.

The day in question was a stormy, summer day.

By 11.30am, the rain was so heavy that visibility had fallen dramatically. Videos captured by security cameras show vehicles slowing down as they crossed Morandi Bridge, which grew progressively more enveloped in a grey mist.

A few minutes later, a 200-metre section of the bridge collapsed, including one of its three supporting towers.

Click the link at the top of this post for an image of the bridge after the collapse.

Reinforced concrete deck, and pre-stressed concrete wrapping the cables of what otherwise looked like a typical suspension bridge. (Think Brooklyn Bridge.) But maintenance of the bridge wasn’t a high priority thing.

A documentary found problems in the 1990s. Riccardo Morandi, the designer, created a list of things to-do to prolong the life of the bridge. Nothing was done.

Aside from the lack of maintenance, there was an increase in the load on the bridge, which is probably a message for engineers, that things should be overbuilt, because you don’t know what the future will bring.

Little, however, was done, and by 1992 the trademark concrete cables were heavily corroded. The company that managed the bridge, Autostrade per l’Italia – then owned by the state – decided to add extra new cables around the corroded ones, rather than replace them. It also neglected to retrofit the remaining two sets.

That led to the collapse on the stormy August morning.

About a year later, the remains of the bridge were demolished. See Genoa’s Morandi Bridge demolished in dramatic explosion. (Explosive demolition is always a fascinating video!)

So why did the bridge collapse?

Instead, it was probably simple neglect that felled the bridge. In April 2018, Autostrade – now a private company – finally decided there was no more time to waste, and issued a tender offer to retrofit the bridge. The repairs were supposed to start last autumn.

“They waited 25 years and then the bridge collapsed. This is how things go in Italy – you start something and you never finish it,” says Saggio.

Today, the new bridge is under construction and it is supposed to be done this year. The replacement bridge was designed by Genoa native Renzo Piano, and is a little more than half complete. Construction of Renzo Piano-designed Genoa Bridge reaches milestone. (There is a video at that link with English subtitles.) The last of the piers have been completed, and the bridge deck is about 550 meters long, just over half of its finished length of 1067 meters. You can find some info on the design at the following link. Renzo Piano unveils design for new Genoa bridge following disaster. It is supposed to be complete in late spring or summer of this year. Let’s hope this one lasts longer.

4 thoughts on “Everything Needs Maintenance – The Morandi Bridge Collapse

  1. When you think about how short a time this bridge lasted.

    The Brooklyn Bridge. Built 1883, age 137 years.

    The Golden Gate Bridge: Opened 1937, age 83 years.

    The Anji Bridge: Finished in 681, age 1339 years

    The Morandi Bridge only stood for 51 years before it failed.

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  2. It is standard practice in the US to design for extreme loads and to apply safety factors to those loads. The Italian bridge was likely under designed, but rampant corruption prevented maintenance.

    Higher traffic volumes do increase wear and tear, requiring increased maintenance, but they do not necessarily increase the magnitude of the peak load, although the duration of that load might increase. But the real issue is the longer duration of the vibrations vibration

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