I can see it happening there... although the design of the PM is a bit different with all the bridge stays going over the lanes.

It's not going to happen everytime it snows... likely a mix of snow/rain/freezing then rapid warming.

Damn, I guess it's the Mission Bridge for me today. I was about to leave for home when a co-worker told me about the bridge being closed.

Of course, the peanut gallery on News1130 has not hesitated from whining about the bridge's design flaws.

The people in this city sometimes...
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Can you blame them though? The bridge is a billion dollar project that has just finished and hasn't even been in operation for a month, and now it happens. Apparently, similar incidents have occurred in the US as well, so it makes you think if the engineers have really done their homework.

If it wasn't a big deal then they wouldn't have shut it down. Billion dollar bridge, implemented tolls, and is now advertised as "the easy and efficient way", and they have to close cause the design team and engineers neglected that we are prone to having snow once in a while.. what a bitch.

you and everyone else :heckno: congesting my streets in ridge :devil:


;)

True. Actually, with the Alex Fraser, I wouldn't be surprised that wind blowing chunks off the cables would be a factor... that design does also have the two cross-pieces between towers, over the roadway. The other similar types of bridges - Pitt River and Golden Ears - don't have any portion of the structure crossing over the roadway.

Yeah, I'd think if it was really that common an issue, we'd see a lot more of it on the other bridges - wouldn't take much wind to blow pieces off and onto the road. Still, with the stays actually going over the road, anything falling off is inherently more dangerous, and they'll have to do something to fix it.

" Hey lets design the bridge have all the suspending cables cross over the entire span of the bridge! :derp:"


I wonder what they're going to do to fix this? Heat trace each suspension cable? lol

So, do you build something that takes into account every freak weather pattern?

Or, do you risk manage and save money and time in the process?

I'm not sure of the choice myself. I challenge someone to give a reasoned answer.
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^^^^ we're a rainforest with storms throughout the year, we get snow every year, is it inconceivable to get what we got last night once or twice a year? not at all (especially since what we got was nothing)

Do it right the first time... Especially a damn public bridge lol... Now they gonna hire more smart asses to figure out a solution for the first fail :P
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Translink is now selling these:

http://www.yourhrexperts.com/blog/wp...er_car-vi1.jpg

:derp:

Any idea when the bridge will be open up again?

between 5 to 7 according to "officials."

People are always quick to assume that the people behind these projects are idiots.

In the public sector, any time public money gets spent for anything, questions get asked hundreds of times before anything gets approved. This issue was probably raised but, based on what has happened, it appears that the design was risk-managed.

I know most of you probably disagree in light of the results, but sometimes, you can't put a square peg into a round hole. The design of the bridge was probably the most cost-effective considering the requirements (width of the span, etc.) I imagine that heat tubes would have added many millions to the project.
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Bitch bitch bitch
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No one is denying the fact that we get snow down here, lest of all the engineers. What we normally don't get, however, is a night of snow and freezing ice, only for it to warm right up after a few hours. Typical weather would allow the ice on the bridge to slowly warm up over time, allowing it to drip off... not fall down in chunks.

No, this is not the first time it's happened in the past (I can remember it happening only once on the old Port Mann in the past), but it happens so infrequently that it's almost a non-issue when it comes to bridge designs down here.

okay, lets take down this bridge and build a new one :troll:

This is Revscene, don't hold your breath.

Actually, it wouldn't surprise me in the least that the situation of ice building up and falling off is found to be a VERY rare result of this specific combination of weather conditions. A half-degree change in temperature either way... a slight breeze while the snow was falling... a fractionally different mix of rain and snow... the smallest thing could have changed and potentially none of it would have happened.

That's the whole idea of risk management: you put in all the known factors, you determine the likelihood that a certain scenario will occur, you figure out what it will cost to mitigate that likelihood... and proceed from there. For all we know, this possibility was known, the chances of it occurring were calculated, and it was deemed it would cost more to prevent than it was worth.

And then again, maybe it's true, with all the hundreds of similar cable-stayed bridge designs in the world, nobody actually thought of this possibility.

Obviously, in standard RS fashion, everyone assumes the latter and that these things spend years on the drawing board under the pencils of barely-trained monkeys rather than several levels of high-priced, well-schooled engineers.

When you think about it, all the old "arch" style bridges have plenty of structure over the roadway as well - lots of room for ice and snow to build up and then fall off. The only significant difference here is that the supports are all sharply sloped, rather than horizontal.

Look at it this way... For not using the bridge, you saved a couple of bucks...go to the dollar store and buy something...russell p. will be proud of you...
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supposedly the eastbound tacoma narrows bridge had to be closed last winter because of the same issue

it was also built by Kiewit

the tacoma narrows' cables don't cross the lanes though





well they do do tests and simulations for ice build-up; and we know now that similar cases have occurred with cabled bridges built by the same company; i agree though that it was probably determined that they would take the risk of it happening

It's not the fault of those who actually built it, either - if anything the problem lies in the actual design, particularly of the cable sheaths, and the material they're made of, all of which allowed the ice to build up. The ones building it have little or no say in that - they're given the plans and they follow what those tell them to do.

The 'perfect' bridge could have been built. But the same people whining about this would instead be bitching about the $20 toll.

It is rather unlucky. I suspect this sort of thing won't happen again anytime soon, even in another snowstorm. It was just an unlucky sort of variables. We'll just have to see.