Pedestrian bridge collapses at FIU

[Cyclones_R_GR8]

A newly opened pedestrian bridge at Florida International University has just collapsed. Details are pretty sketchy at this time. According to this article the bridge was designed as part of a program offered at FIU

http://www.miaminewtimes.com/news/fiu-pedestrian-bridge-collapses-in-miami-10176573

 

[srjclone]

Wow, that is a scary sight seeing those cars smushed under the collapsed concrete.

 

[Tri4Cy]

Opened on Saturday. Collapses on Thursday. Not good!

 

[mj4cy]

Was just about to post this. Ugh. Heart goes out to the families/those that were injured/killed.

As a structural engineer, my first thought beyond the people involved goes to the cause. Was it a design flaw? Construction flaw? Time will tell.

 

[Doc]

Was just about to post this. Ugh. Heart goes out to the families/those that were injured/killed.

As a structural engineer, my first thought beyond the people involved goes to the cause. Was it a design flaw? Construction flaw? Time will tell.

It's always construction's fault, right

 

[DeftOne]

The bridge was designed by Figg Engineering, who are world-renowned bridge designers. They also designed the new I-35W bridge in Minneapolis.

The "program offered at FIU" is just referencing the Accelerated Bridge Construction (ABC) part of the project, which FIU has been a leader in for many years. For this particular bridge the ABC portion was building the main span off on the side and moving it into place using Self-Propelled Modular Transports (SPMT's).

 

[mj4cy]

I know you're joking, but in my experience, I've seen issues on both sides. As a design engineer, you wouldn't believe the critical things I saw on observations that were missed by contractors.


That's not to say engineers over the years haven't made fatal mistakes as well (gusset plate design at the I-35 W bridge in Minneapolis - or the Hyatt Hotel in KC).


Key is communication. An engineer is only as good as the product put in the field. The better his drawings/calculations are along with communication during construction, the more successful the project.

 

[CtownCyclone]

I'd imagine the bridge would have been modeled and checked for stresses, right, structural guys?

 

[alarson]

 

[cyhiphopp]

****. Why didn't they close the dang street?

 

[carvers4math]

There are so many sinkholes in Florida, I would wonder about solid footings for the bridge. It’s developing a swamp.

 

[knowlesjam]

Seems like a lot of bridge span length for the amount of run-up and support at each end, but I'm sure they tested the span strength. Maybe an issue at the connection point?

 

[Cyclones_R_GR8]

This looks like some sort of major flaw in the installation plan. They just put this section into place last Saturday. Now judging from the model there are supposed to be suspension cables to support the entire structure but those weren't in yet. So it appears they removed all the supports holding it up so traffic could continue on Monday leaving that long span to just support itself.

https://news.fiu.edu/2018/03/first-of-its-kind-pedestrian-bridge-swings-into-place/120385

 

[3GenClone]

Seems like a lot of bridge span length for the amount of run-up and support at each end, but I'm sure they tested the span strength. Maybe an issue at the connection point?

That's what it looks like in the photos.

 

[CyArob]

It's always construction's fault, right

Yes, that's correct.

 

[CyArob]

This looks like some sort of major flaw in the installation plan. They just put this section into place last Saturday. Now judging from the model there are supposed to be suspension cables to support the entire structure but those weren't in yet. So it appears they removed all the supports holding it up so traffic could continue on Monday leaving that long span to just support itself.

https://news.fiu.edu/2018/03/first-of-its-kind-pedestrian-bridge-swings-into-place/120385

View attachment 54003

That would be quite the oversight on someone's part

 

[Doc]

This looks like some sort of major flaw in the installation plan. They just put this section into place last Saturday. Now judging from the model there are supposed to be suspension cables to support the entire structure but those weren't in yet. So it appears they removed all the supports holding it up so traffic could continue on Monday leaving that long span to just support itself.

https://news.fiu.edu/2018/03/first-of-its-kind-pedestrian-bridge-swings-into-place/120385

View attachment 54003

Wtf? It looks like the only thing holding it up was the deck.

 

[Cyclones_R_GR8]

That would be quite the oversight on someone's part

I know but I am just going by what I can see in pictures and making a guess. We'll have to wait for the official statement. Not sure how many people were injured or worse. Awful situation. I can't imagine how all the people involved feel.

 

[alarson]

This looks like some sort of major flaw in the installation plan. They just put this section into place last Saturday. Now judging from the model there are supposed to be suspension cables to support the entire structure but those weren't in yet. So it appears they removed all the supports holding it up so traffic could continue on Monday leaving that long span to just support itself.

https://news.fiu.edu/2018/03/first-of-its-kind-pedestrian-bridge-swings-into-place/120385

View attachment 54003

Yeah, i'm no engineer but from my extensive bridge builder game experience that seems like a **** up.

 

[Cyclonepride]

This looks like some sort of major flaw in the installation plan. They just put this section into place last Saturday. Now judging from the model there are supposed to be suspension cables to support the entire structure but those weren't in yet. So it appears they removed all the supports holding it up so traffic could continue on Monday leaving that long span to just support itself.

https://news.fiu.edu/2018/03/first-of-its-kind-pedestrian-bridge-swings-into-place/120385

View attachment 54003

So it was missing the whole suspension portion? I'm not an engineer, but that seems like a terrible idea to open it to any traffic on or under until that was up.