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Bridge Collapse in Italy 2

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Halving joint, or corbels, are always a weak link if not done right. There have been many failures of this type joint. Luckily, most have not led to fatalities like this one. There is now better understanding of corbel design (by strut and tie methods), but the bridge in Italy was doubtless designed and built a long time ago.
 
A bridge that's in trouble and they allow a 108 tonne truck to drive over it? That's nearly 2½ times the weight of the largest 'standard' trucks on European roads. Very bad luck for the folks driving beneath the bridge.
 
With news coming in of another big earthquake a couple of hours ago, the fallout from this story might not get the Italian media attention it deserves.

A.
 
It's hardly a 'stationary position' as it appears to have been taken using a handheld camera/cellphone. That being said, it does seem strange that someone was actually shooting a video at that particular moment considering that nothing extraordinary looking was happening prior to the actual collapse of the bridge, although it does appear that the camera position, if it was not a handheld unit, was in a lane that had been 'coned-off' for some reason so I guess it could have been a temporary webcam set-up to observe traffic patterns near where some sort of road repair was underway.

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If you watch the LiveLeak footage, you'll see that the original footage seems to have been taken from a stationary camera - watch the left hand side of the moving image - you can see that it remains fixed in frame, indicating a stationary camera got the original footage. It looks like a fixed camera had indeed been installed (which is probably why the cones are there - it looks like the camera is installed on the roadway), and somebody has leaked the footage by taking a hand-held copy from a TV screen and released that.

 
The video makes it horrific. Where I live the road inspectors/contractors have authority to close bridges in these situations with a phone call.
 
I wonder whose cones those are closing off the lane below?

Unless they were already there for some other reason, they make you suspect that somebody already believed they had authority to close at least part of the road.

A.
 
I think the cones were there because chunks from the bridge had fallen into that lane.

on the same note, but thankfully no events to make global news were the inspections of bridges and culverts around home following the flooding from "Mathew". A friend of a friend worked for the State and put into emergency service to take photos ahead of the engineers (sort of a triage). his comments were many would have soil falling when traffic passed and he could not, nor had the means to close the roads. there was one exception though where he did stop the truck, made the drive look at the culvert to convience him to back up. Local papers/news showed several incidents of vehicles dropping into washouts.
 
"The bridge, in Lecco, fell when a heavy goods vehicle, weighing 108 tonnes..."- I note that the truck doesn't look like one that would normally weigh 108 tonnes, and suspect something is off there.
 
Looking at the video, I thought that at first - but then took a closer look at the stills in the Metro report linked in the OP.

There, you can see:

What looks like a 6x4 tractor (rather than the 4x2 that's common on the Continent or the 4x2 + lifting tag axle popular in the UK)

At least 4 axles on the trailer with the possibility of another out of view.​

Making a few assumptions:

18 Tonne for the tractor unit

13 Tonne tare for the trailer (assuming 4 axles and no ramps)

15 Tonne capacity for each trailer axle (assuming we're into heavy haulage territory) x4

Tractor Trailer combination loaded up to the limits

Trailer tare weight carried by the tractor and load borne entirely on the trailer axles (this sounds odd but, with the perennial difficulty of getting enough weight to transfer onto the fifth wheel - look how far forward they've placed the load in the pictures - is usually a good working approximation)​

I'm already at 91 Tonnes (a lot more than the 44 of your everyday artic) with the possibility of 107 if there's a fifth axle hidden behind the wreckage of the rear curtainside frame. Not a million miles off the reported figure.

A.

 
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