And thoughts and prayers.
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Well it is too soon to talk about bridge control.
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bbc says that the design was a quick build so as not to hamper traffic flow
looks to me like the re-inforcement was left out if the piers where of the correct proportion… otherwise the wholly overall look of the design gives doubts on the classical styling is bottom heavy which might say it was assembled up-side-down
I love that there are people who are part of this community who are super smart on things like this. Thanks for being here, I hope you never have to be a part of this sort of thing in your professional life.
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Hers was not, my rapidly developing one is. I’m not so sure mine is a real phobia as much as it is a response to my nation’s obviously rickety infrastructure.
The I-35 bridge collapse in Minnesota a decade ago freaked me out and continues to do so.
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I have to walk back my doubts about the bridge being the design that had the pylon and the cables.
Looking more closely at the pictures of the collapse it appears that there are raised areas on top of the top of the bridge that look like they would have received the cables from the pylon.
This raises questions about the sequence of construction and the strength of the bridge. It was obviously set in place without the pylon and support cables, which means it had to be designed to be strong enough to support itself without the pylon and cables. That in itself sounds redundant. It means either the pylon and cables were superfluous and unneeded structurally, or it means this leg of the bridge was not designed to be strong enough to span the distance without the pylon and cables, yet it was installed that way.
Yet it seems unthinkable that they would place the bridge there without calculating whether it was capable of supporting itself. Are we certain that temporary intermediate supports were not left in place after the bridge was place?
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I’m going to go out on a limb based on my personal contracting experience and all the structure failures I’ve ever read about, and say it was contractor/worker error not design error. The design tools available today are unbelievable, and allow the design to be checked easily. Workers and subs on the other hand, are often all over the place, and inspectors are often uninterested in anything but rubber stamping, especially when they have “good relations” with the contractor. Remember that thread about architectural screwups like doors leading to thin air and balconies with no doors?
Actually, that’s a legitimate way to build a short cable-stayed bridge. As an example,
The prefab structure of the bridge is suspended in place before the main support tower is even installed, let alone the cables.
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I was wondering about that. I’ve never worked on something nearly so large and dangerous but I have done plenty of remodels and additions, and structural work is always reinforced until complete installation. And I’d imagine with something like this you’d be extra cautious.
Yes - the deck is placed before the cables are installed, but note there are temporary supports at the place where the two decks join, and they remain in place until after the cables are all done, in fact its the last thing to be taken away.
Plus that video the entire bridge was installed overnight. Its not like they set the deck without the cables and left it there for days.
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im amazed that there were no temporary supports in the middle.
Pedestrian bridge is -full- of antiviral medication, but ah, what file did you print again?
If there were running bridge sensors (as expected for a first install) one would’ve hoped the data dropout would precede an event. Lol, fingering Analytics Group at the architects’ office.
‘Florida Bridge smashes 6 cars plus, throws pedestrians’ would have flown without notice.
Same ol’…
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I could have sworn there was a support in the middle, but I can’t seem to find images of the structure before the collapse, but after it was lowered into place.
I’ve seen cable-stayed bridges that were left without tensioned cables for long periods of time, though. In this case, the superstructure was precast concrete… most of the load (infrastructure, deck, ballast) was installed only after the cables were tensioned, though.
I can see an argument otherwise in this case. If no-one got the contract than there would have been no bridge to collapse.
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From the rendering, it looks like this span was only one half (the larger side) of the bridge, which also explains the asymmetric diagonal bracing with exposed tops that would have tied into the cables.
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I’m afraid that the government has two extremes as far as funding projects go, they will either wastefully overspend or will look for the cheapest shittiest way to complete it. Its criminal that people died in this collapse and i’m curious who exactly will get the brunt of the blame, but i would presume many people are involved and responsible.
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I first read about Accelerated Bridge Construction almost five years ago when Wired did an article about a bridge replacement between NY and CT.
I still remember it because of the comment I made at the time:
Hello drivers, look at your bridge, now back to me, now back at your bridge, now back to me. Sadly, it isn’t me, but if it stopped using haphazard repair methods and switched to ABC, it could drive like me. Look down, back up, where are you? You’re on a crane with the bridge your bridge could drive like. What’s in your hand, back at me. I have it, it’s an interstate with two lanes to that place you love. Look again, the two lanes are now four. Anything is possible when your bridge is replaced by ABC and not standard construction. I’m on a bulldozer.
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isn’t that a myth?
the gsa ( quick google search ) for instance says this:
The basic method requests both Technical or Management Proposals and a Price Proposal. Once the proposals are received they are evaluated technically, and then evaluated in terms of prices.
the idea that government agencies literally goto the lowest bidder is absurd.
you would have joe and jane schmo saying they could do a million dollar road project for 10k. and we’d all just have to deal with it.
that’s part of why so many republicrats want deregulation. to ship money to their friends. if they could just give insider information to offer 1 dollar less than x, they wouldn’t have to deregulate.
( also why wars are so popular. that money goes literally anywhere. it’s a war zone in another country. regulation be damned. )
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$14,200,000 seems like a lot of money to spend on a pedestrian bridge but I admit I know little about bridge building costs. Would someone who does know about these things kindly comment on the cost?
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The possibility alone of maybe sliding seeingly into a phobia is horrible.
