This may well be one of the few engineering disasters where someone goes to jail for actions they did or did not take.
FIU ped bridge collapse. Your thoughts.
- Thread starter hitchicken
- Start date
This may well be one of the few engineering disasters where someone goes to jail for actions they did or did not take.
PeoplesElbow
Well-Known Member
I am betting that the tension lines were either not properly tensioned, or that whatever holds them to the span was not properly attached and slipped so the concrete was under tension. Concrete is very strong in compression but pretty weak in tension, the reason for prestressing concrete with steel rods that squeeze it. I bet moving the span into place on those crawlers caused some damage that started this process.
I also don't like the sound of "self cleaning concrete" as it reminds me of self cleaning paint that chalks off to expose clean paint.
I wonder if the engineer left the message on the only persons phone that he was required to. I know people at work that refuse to leave an out of office message on their phone and email, my supervisor yells at us when we don't do it.
littlelady
God bless the USA
I hope so. Watching and seeing those cars in the wrong place at the wrong time, in a matter of seconds and ending lives is, incredibly, sad. It goes without saying that this tragedy should have never happened, and someone(s) should pay; so to speak. Prayers to the families.
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Most of these cable-stay bridges with a pre-tensioned concrete deck are built piecemeal. They put up the tower first and add short pre-stressed segments supported by a large 'bridge building machine'. Building the bridge deck in one piece and moving it into position was supposed to reduce the number of road/lane closures and the risk from having to hoist individual bridge segments above a busy highway.
But you knew that ;-)
That bridge was supposed to improve air quality on Tamiami Trail. You can't make this up.
A lily white bridge like that on a university campus just screams 'tag me' and it would have been covered in moronic graffiti a week after its finished.
This will be interesting to see who else at FIGG (the engineering firm) and MCM (the local contractor) was informed of the cracks and the pre-tensioning cables going slack. In the voicemail the engineer talks about 'we' don't think its a safety issue. I would like to know who 'we' are, because 'we' were wrong.
The irony is that this company has been involved in huge successful projects like the Zakim bridge and the seven mile bridge. And now they are going to be in major trouble for what in the world of bridge building is a little bull#### project.
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PeoplesElbow
Well-Known Member
Sort of makes me wonder if it was thought of as not that important so they put someone inexperienced in charge or something like that. I would think the person would have had to be a PE, maybe not. I also wonder what the safety requirements for a pedestrian bridge vs a vehicle bridge are.
BOP
Well-Known Member
The comments are probably the most entertaining part.
http://www.foxnews.com/us/2018/03/1...florida-bridge-as-reports-cracks-surface.html
As reports emerged about an engineer's warning of cracks days before Thursday's calamitous collapse of a pedestrian bridge in Florida, a U.S. senator wants to find out exactly who was behind the construction that may have led to the structure's fatal failure.
Sen. Bill Nelson, D-Fla., ranking member of the Senate Committee on Commerce, Science and Transportation, is “demanding” documents related to oversight of the construction of the bridge at Florida International University in Miami, according to a statement from his office.
http://www.foxnews.com/us/2018/03/1...florida-bridge-as-reports-cracks-surface.html
As reports emerged about an engineer's warning of cracks days before Thursday's calamitous collapse of a pedestrian bridge in Florida, a U.S. senator wants to find out exactly who was behind the construction that may have led to the structure's fatal failure.
Sen. Bill Nelson, D-Fla., ranking member of the Senate Committee on Commerce, Science and Transportation, is “demanding” documents related to oversight of the construction of the bridge at Florida International University in Miami, according to a statement from his office.
LightRoasted
If I may ...
If I may ...
Of any pre-tensioned/pre-stressed bridge section I've ever seen, they always have a bit of an upward concave curve to it. Never completely flat, as this span was. Which leaves me to believe that no matter even if tension cables were tight with sufficient lateral forces, it still would have snapped like it did, before installation of any support cables, due to gravity and the vertical force load in addition to being made entirely of concrete, even the over head roof.
Of any pre-tensioned/pre-stressed bridge section I've ever seen, they always have a bit of an upward concave curve to it. Never completely flat, as this span was. Which leaves me to believe that no matter even if tension cables were tight with sufficient lateral forces, it still would have snapped like it did, before installation of any support cables, due to gravity and the vertical force load in addition to being made entirely of concrete, even the over head roof.
This was supposed to be some new construction technique for putting a bridge in place quicker.
I don't think there was supposed to be any supports or cables (per the design), from what I read it was to "swing into place.
Have not seen pictures of the bridge either before or after the collapse. But from what I've read it would have had an arch or cantilever to transfer the weight to the load bearing buildings.
Now they are saying there were cracks, but they did not compromise the structural integrity of the bridge.
[video=youtube;Ik1fCeo4CpQ]https://www.youtube.com/watch?v=Ik1fCeo4CpQ[/video]
The bridge section that collapsed is designed to hold its own weight until the entire span is assembled into place, Verrastro said. It was built under a method called accelerated bridge construction, which FIU helped to popularize beginning in 2010 but has been around in some form for about 30 years.
LightRoasted
If I may ...
If I may ...
You know what this bridge span reminds me of? When you are trying to stretch out a measuring tape to another wall until you reach that point where it snaps and falls to the floor under its own weight just before you get it to the other side. That's what happened here.
You know what this bridge span reminds me of? When you are trying to stretch out a measuring tape to another wall until you reach that point where it snaps and falls to the floor under its own weight just before you get it to the other side. That's what happened here.
It collapsed.
Lurk
Happy Creepy Ass Cracka
More flowers, that's apparently what the concept was lacking.
They do need the pedestrian bridge...regardless.
If the crane is still there... Swing across.
There are companies who will deliver and assemble a complete steel bridge on site. It won't save the polar bears or clean the polluted Miami air, but it'll carry pedestrians and bicycles across the highway.