Catastrophic Bridge Collapse in Genoa, Italy

[Busy Bee]

I've started a thread for the bridge collapse tragedy in Genoa, Italy for discussion as news unfolds. There will likely be months of engineering investigations to find the cause and this shocking event has all the signs of being one of the worst civil engineering failures in history. As of 2pm, Tuesday, Aug 14, fatalities stand at 35.

[Busy Bee]

Italy bridge: Dozens feared dead in Genoa as motorway collapse




A motorway bridge has collapsed in the northwest Italian city of Genoa and fire brigade sources say 35 people were believed killed as vehicles plummeted to the ground.

Dramatic video footage captured the moment of the disaster when one of the huge supporting towers crashed down during torrential rain.

Vehicles and debris fell 45m (148ft) on to rail tracks, buildings and a river.

Searches for people trapped in rubble are expected to go into the night.

Fears that other parts of the bridge might fall have prompted the evacuation of buildings in the area, a rescuer told Italy's Ansa news agency.


https://www.bbc.co.uk/news/world-europe-45183624




Dozens Of People Feared Dead After Span Of Busy Highway Bridge Collapses In Italy




A long section of the towering Ponte Morandi Bridge completely collapsed in Genoa, Italy, on Tuesday, sending cars and trucks on the A10 highway crashing down below. Dozens of people died in the bridge failure, officials say.

As news emerged from the chaotic scene, the death toll fluctuated several times Tuesday. Prime Minister Giuseppe Conte said there were 22 dead, according to public broadcaster Rai News. But Italy's ANSA news agency has reported at least 35 people died, citing the fire brigade.

Workers have found bodies and vehicles in the massive amount of wreckage left by the collapse — and at least 11 people have been pulled from the rubble alive, Italian media report.


https://www.npr.org/2018/08/14/63846...apses-in-genoa

[CastleScott]

^ This brings me back to the bridge that collapsed into the Mississippi River in Minneapolis back in August 2007.

[ardecila]

I had not heard of this bridge designer, Riccardo Morandi... Italian engineers always have the funkiest designs, from the masterworks of Nervi to the Musmeci bridge in Potenza.

The Minneapolis bridge was a very unremarkable bridge, there are 700 similar bridges around the US. The failure was found to be in the undersizing of certain steel gusset plates at the joints in the truss. However, the Morandi bridge in Genova was a highly experimental design. Most engineers since have looked at Morandi's designs as a dead end of engineering, since they do not provide any redundancy if one of the stays were ever to fail.



Morandi built this uber-brutalist monster in Venezuela, very similar to the Genova bridge but longer and taller...

[plinko]

^THAT'S where I've seen this design before. I was trying to place it. Maracaibo (which I've actually seen in person).

[redblock]

Here is the Wikipedia page.

https://en.wikipedia.org/wiki/Ponte_Morandi

Scroll down some. One of the pictures shows the intact bridge and what collapsed. It includes a third tower.

[Steely Dan]

what a terrible tragedy.

i'll be very curious to see what the investigation discovers as to how such a seemingly robust bridge structure collapsed so catastrophically.

[Pedestrian]

Supposedly this thing collapsed in a "bad storm". Hard to believe a storm could bring down a reinforced concrete bridge like this. There has to have been either a design flaw--such as with the infamous Tacoma Narrows Bridge--or a maintenance issue that we don't yet know about. I know out here in SF, they have tried to add rigidity to the Golden Gate Bridge which is routinely subject to 70 mph plus winds to prevent something like Tacoma Narrows.

The Tacoma Narrows Bridge:

• Video Link

[Busy Bee]

There is some chat over at SSC speculating that the temporary concrete barriers (Jersey barriers) on the bridge during it's refurbishment added more than 400 tons to the span that collapsed. Seems like a worthy candidate for possible contributing cause.

[Pedestrian]

Autostrade per l’Italia, the company that runs the highway, said work had been in progress to improve the bridge’s foundations. The bridge was under “constant” monitoring, the company said . . . .

Italy has struggled in recent years to keep its infrastructure, both public and private, well-maintained. Last year, a bridge over the highway running along the Adriatic coast collapsed, causing two deaths, and in 2016 a bridge on a busy road north of Milan fell, leaving one dead and five injured.

More than 30 buses in Rome have spontaneously caught fire in the past four years due to a lack of maintenance . . . .

Autostrade per l’Italia is a private company that receives government commissions to run toll roads . . . .

https://www.wsj.com/articles/italian...d=videorelated

So something was wrong with the foundations?

[Busy Bee]

43 fatalities

https://www.usatoday.com/story/news/...al/1030356002/

[mousquet]

Originally Posted by ardecila

Morandi built this uber-brutalist monster in Venezuela, very similar to the Genova bridge but longer and taller...

This bridge in Venezuela partially collapsed only a couple of years following its opening.
And another bridge by the same engineer has been closed for years in Sicily, because of structural shakiness.

This guy Morandi had an original approach that all other influential structural engineers turned down.
I heard his bridges were designed as independent components eventually assembled on site.
It sounds like a smart idea; some concept working fine in a number of various tech fields, like electronics and software engineering in particular.
But it wouldn't work to something as sensitive as bridges. Now everybody's aware.

[mousquet]

Originally Posted by ardecila

However, the Morandi bridge in Genova was a highly experimental design. Most engineers since have looked at Morandi's designs as a dead end of engineering, since they do not provide any redundancy if one of the stays were ever to fail.

This is utterly interesting. Perhaps if they agreed on some kind of standard, like a common construction interface of some sort, Morandi's idea would actually work and allow some innovative aesthetics or some efficient methods based on precast materials.
I suspect it was his initial idea.

But there's a lot of prestige for a single engineer in building a bridge. It is certainly the finest art of their science. Buildings, including skyscrapers would actually be easier to design, because structural constraints would be softer.

So there's got to be a lot of pride in there, which doesn't help people cooperating to establish regular standards.

[ardecila]

Originally Posted by mousquet

This bridge in Venezuela partially collapsed only a couple of years following its opening.

It collapsed because an oil tanker ship ran into it, not because of a structural failure. Supposedly it has been reinforced, but that's what they said about the bridge in Genova.