breaking news- bridge collapse in Miami

[kevo_55]

Whoa, sad news.

All I can say is that someone's license is going to be taken away.

 

[MA_PE]

This site has a video of the actual collapse.  It seems to have just folded.  No appreciable warning at all.  It'll be interesting to see the details of this design and its construction that led to a completely brittle collapse.

https://www.cnn.com/videos/us/2018/03/16/video-of-florida-bridge-collapse-sot.cnn

 

[matt267 PE]

Stress test may have contributed to collapse of FIU pedestrian bridge

http://www.miamiherald.com/news/local/community/miami-dade/article205422719.html

So what actually goes into a "stress test" for this type of bridge?

 

[MA_PE]

http://www.miamiherald.com/news/local/community/miami-dade/article205422719.html

So what actually goes into a "stress test" for this type of bridge?

just news jargon.  Stress tests are what you do on a treadmill to check your heart.

 

[matt267 PE]

just news jargon.  Stress tests are what you do on a treadmill to check your heart.

Ah, ok. I did read this morning from an other article that "engineers" noted that some cables had come loose and needed to be tightened. There were 2 workers on the bridge doing this work when it collapsed. 

https://www.usatoday.com/story/news/2018/03/16/authorities-miami-bridge-collapsed-cables-were-being-tightened-following-stress-test/431392002/

And they keep using the term "stress test."

 

[Road Guy]

The firm that did the design also designed the "sunshine skyway bridge" in Tampa - so you would like to think they know what they are doing?

 

[MA_PE]

Ironically, FIU has an accelerated bridge program

https://abc-utc.fiu.edu/

this won't help the program much.

 

[matt267 PE]

Ironically, FIU has an accelerated bridge program

https://abc-utc.fiu.edu/

this won't help the program much.

Are you suggesting the accelerated bridge program will fail its "stress test" too? 

 

[MA_PE]

I'm sure they are under a lot of stress

 

[Road Guy]

No one has any patience to follow the traditional process anymore. Sometimes (owners of the projects, government, private, etc) people just need to be willing to slow down and operate at a normal pace.  these days no one wants traffic impacted, or delays to students walking to school, but the focus on these types of projects usually revolves around what the quickest / fastest way to do this is without making anyone suffer travel delays through lane closures..

I am sure this idea was pitched as an awesome "overnight" way to get the bridge up, but what would the real impacts have been to doing this "the old fashioned way" (which is usually the way that works best) I mean you could have close the road at night to set some traditional beams, there was room to build a center support structure - but that wouldn't have been "sexy"...

 

[MA_PE]

No one has any patience to follow the traditional process anymore. Sometimes (owners of the projects, government, private, etc) people just need to be willing to slow down and operate at a normal pace.  these days no one wants traffic impacted, or delays to students walking to school, but the focus on these types of projects usually revolves around what the quickest / fastest way to do this is without making anyone suffer travel delays through lane closures..

I am sure this idea was pitched as an awesome "overnight" way to get the bridge up, but what would the real impacts have been to doing this "the old fashioned way" (which is usually the way that works best) I mean you could have close the road at night to set some traditional beams, there was room to build a center support structure - but that wouldn't have been "sexy"...

nothing wrong with the accelerated bridge concept.  I'm not getting where the cables some into play here, but I suspect it's the fundamental concept of the bridge design that did not' mesh well with the accelerated process of setting it in place in one piece after construction.

Here is MA they replaced a bunch of generic steel girder concrete deck overpasses following the ABC process.  Closed the road for a few hours each weekend when they hoisted them in-place.  Worked beautifully with minimal traffic impact.

 

[Road Guy]

It does have its place, but I would argue that a new ped bridge doesn't really have the same urgency as replacing a roadway bridge which is open to traffic and you have massive impacts to the surrounding network when the bridge is out..

I think smaller government entities, including colleges like to use alternate delivery as a crutch to overcome their pro longed decision making skills (or lack of the ability to make one)

For example I'm writing a Design Build Manual for a friggin BIKE program right now.. jesus h Christ! & Mainly because the "staff" has fucked around for 4 years and not delivered any projects or initiated design - so viola - Alternate Delivery to the rescue -

 

[MA_PE]

II would argue that a new ped bridge doesn't really have the same urgency as replacing a roadway bridge which is open to traffic and you have massive impacts to the surrounding network when the bridge is out.

With six lanes of traffic below this pedestrian bridge I suspect that its a busy road and closing lanes to construct the bridge would certainly impact traffic here.

 

[matt267 PE]

With six lanes of traffic below this pedestrian bridge I suspect that its a busy road and closing lanes to construct the bridge would certainly impact traffic here.

Well, it's certainly impacted now. 

 

[Road Guy]

Yeah that's my point, but even with a traditional design you'd really only need to close the road trip one night to set the beams and maybe put the metal decking in place, outside of that it just would've been some daily lane closure headaches

 

[MetsFan]

The firm that did the design also designed the "sunshine skyway bridge" in Tampa - so you would like to think they know what they are doing?

Looks like they also designed the Zakim bridge here in Boston.

 

[Road Guy]

my vote is going to be either an error in the fabrication process or something contractor related