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Rail bridge collapses near the US-Canada border 9

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Looks like the counterweight support structure gave way allowing face-plant on the far side.
bridge_n7eged.png
 
Agree, Dave. Must have made a helluva noise when that span came down on the abutment. Looks like some web buckling near the end, but mostly just bending deflection.
 
Pure speculation, but I winder if the control room convesation went something like this;
"Charlie. How many times do I have to tell you?
You have to retract the dogs and wedges before you engage the lift."

--------------------
Ohm's law
Not just a good idea;
It's the LAW!
 
I would expect that there was an interlock which would have not allowed the counterweight mechanism to engage if the 'dogs' had not been disengaged.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without
 
What surprises to me is how rapidly railroads respond to incidents. It's like they have drawn up plans for every possible situation and have equipment and material at the ready.

Of course, they also seem to have situation that they don't do as much preventive maintenance as one might expect, but I just saw a water main repair of a break from 4 months ago that left a major intersection with a rather large hole, maybe 40 foot by 40 foot by 10-15 feet deep; completely impassible.

Rail road repair seems like that would be 2 days and ready to use.
 
Like many utility companies, there is a limited amount of equipment and supplies staged around to respond to emergency conditions. What company of this size would not do that?
Besides with so much older rail removed in this country, and so few spare rail routs, why not pay more attention to the few problems you have. And the hold up of shipments is money sitting that can't be made.
 
My comment was made partly in jest, David.
Looking at the latest pictures posted by Human909 it appears that the counterweight is passive.
That is, it does not move with the drawbridge as the span opens.
The counterweight position does not change as the drawbridge opens.
It appears that the span may be opened a crown and pinion gear set.
A more serious suggestion is that this may have been a corrosion issue.
I wonder if someone in the maintenance and inspection planning department has MBA training?


--------------------
Ohm's law
Not just a good idea;
It's the LAW!
 
Its actually here
So 5 mles from international falls onthe Canadian side of the border, not rainy river.

Looks to me like it was left int he up position as a default to allow boat traffic under

We can only assume the connecting rods failed for some reason.

Not sure how it operated though - difficult to find any information it. You can / could see it fromt he highway accross the lake if you go into street view.

Looks like they are busy repairing it any way. Old structure already gone!

456949372_1000820825263044_7042133140562837157_n_mplruy.jpg


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Oops409. The pictures you have posted above are not the same bridge. It is a nearby bridge but not the same one.

waross said:
The counterweight position does not change as the drawbridge opens.
It appears that the span may be opened a crown and pinion gear set.
Yes that was what I thought. I'm not familiar with too many types of raising bridges so I thought I may have been stating the obvious.

It does seem to be a method that is very demanding on the mechanics. It did well to survive the time is has done.

waross said:
We can only assume the connecting rods failed for some reason.
There doesn't seem to be any connecting rods to fail.
 
I don't think anything moves in the counter weight.

It's pretty clear that the "normal" position of the bridge is open. Every shot you see has it open. So this is where everything is in a "neutral" position.

SO I think the thing is just very well balanced and rotates around its hinges with minimal hydraulic effort - so a bit like Tower Bridge in London and a lot of these bascule bridges.

If a train went over it apparently according to old Casey just before they heard a bang it sounds more like this was on the opening procedure and the counter weight mechanism just seems to have completely broken free of the bridge structure and fallen backwards with the bridge at maybe part height then falling and collapsing.

So corrosion hidden in the structure seems a more likely explanation. The thing looks to b similar to the 1908 bridge so over 100 year sold, next to a lake and where it gets pretty cold in winter and hot in summer.

If this is the same bridge "5 mile bridge being 5 miles from Fort Frances, then it had problems with the bearings 5 years ago.

Note a lot of sites call it the rainy river rail bridge. It isn't, its the 5 mile bridge. The rainy river one is in fort frances itself and is quite different.




Remember - More details = better answers
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In the London Bridge, the weight rotates with the bridge. But that requires room underneath for the weight to go. This is too close to the water for a pit large enough.

Note the tilt of the upper counterweight support matches the tilt of the bridge and that the lower counterweight support isn't one that would be stable; it's on a V with the point down.

bridge3_bhvzbj.png
 
It's a bit confusing because the house is behind it and I've found a GE image of the bridge down and fair enough, the counterweight thing doesn't move with the bridge, but does seem to go up and down.

If you go to GM and streetview on the bridge and then different dates and then move along the bridge you see it move and the weight goes up. So maybe some sort of hydraulic lift or just a mechanical connection resting on the end of the semi circular end of the bridge.

Actually int he side view you can see the struts connecting the weight to the bridge and the weight to the lattice structure. So it hods it vertically as it moves.

Screenshot_2024-08-29_182604_stxorh.png
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Also: If you get a response it's polite to respond to it.
 
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