bridgebuster
Active member
Looks like a shear failure of the seat; I've seen that before.
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Bridge Collapse in Italy 2
- Thread starter bridgebuster
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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.
TehMightyEngineer
Structural
Wow, looks like they even saw it failing and tried to shut down the road. I'm very curious to see how this plays out.
Professional Engineer (ME, NH, MA) Structural Engineer (IL)
American Concrete Industries
Professional Engineer (ME, NH, MA) Structural Engineer (IL)
American Concrete Industries
There is some video of the bridge collapsing, taken from a stationary position, as if the collapse was expected.
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JohnRBaker
Mechanical
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.
John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
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UG/NX Museum:
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John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:
The secret of life is not finding someone to live with
It's finding someone you can't live without
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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.
allgoodnamestaken
Structural
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 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.
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.
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:
Making a few assumptions:
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.
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.
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)
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.
I believe you're right, I was judging off the video, where the truck appears similar to an American 18-wheeler, which would normally run around 80,000 lbs.
Another video here appears to show 5 axles on the trailer:
Another video here appears to show 5 axles on the trailer:
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