Miami pedestrian bridge collapse

[Peter 315]

8 lane highway + college students + cell phones = problems.[/QUOTE

 

[CincyFlyer]

So this guy is under the bridge when it makes a snapping noise 5 hours before it fell. Then, there was a meeting of the minds 2-3 hours before it fell. Was there ANYONE worried about the cracks?
Miami FIU bridge collapse: Man hears crack before collapse | Miami Herald

All. Concrete. Cracks. All.

 

[ruffdog]

Now they are saying the DOT ordered the north support to be placed 11 feet further north (oct 2016). That not only delayed the project, but the span had to be redesigned on the end that failed.

Florida bridge collapse: Design change put project behind schedule, millions over budget - CBS News

 

[ruffdog]

All. Concrete. Cracks. All.

The cracks must have been bad enough to be the subject of a voicemail and a special meeting.

 

[CincyFlyer]

The cracks must have been bad enough to be the subject of a voicemail and a special meeting.

Perhaps, but it's likely that they were not critical, if one judges by the tone of the email. It's possible that handling the bridge section in a manner other than designed (not at the far ends) caused an issue. We'll see; this is sort of like guessing the cause of a plane crash; a zillion theories, and the answer usually involves more than one of them—a chain of events.

 

[California]

Eng-Tips has a whole lot of discussion, speculation, hypotheses by engineering professionals, that is more insightful than what we have in this thread.

Also much better photos.


Eng-Tips . com - Forums by Industry > Forensic Engineering > Engineering Failures & Disasters Forum

Miami Pedestrian Bridge, Part II - Engineering Failures & Disasters - Eng-Tips


One example: speculation that a 9 inch drain in the deck was the initial point of failure.

 

[Shield Arc]

I've worked on several bridges. In Washington, and California. I never was involved in the pre / post tensioning. Iron workers do that. I've drove thousands of concrete piles. They are pre-tensioned with strands. Good rule of thumb is never hit the concrete pile over 100-blows per foot with the pile driving hammer.
This is a picture of my oldest granddaughter at the Port of Oakland. She is 24-years old now.

 

[coldsteelva]

Always an expensive solution just looking for a problem. How long has FIU been in that location? One pedestrian was struck and killed so you spend 100s of millions to design and construct a bridge using 'innovative' (unproven/untested) design and so you don't detour a few people, you make the unproven/untested/unstable bridge 'portable'. This leads to the death of 6 people, injuries to others, 100s of millions wasted and millions more coming in pending lawsuits and fines. All because a single person either crossed against traffic OR had the right of way, but was dead right.

How much could have been saved, if they simply put a better set of traffic/pedestrian signals? So wasteful.

 

[CincyFlyer]

Always an expensive solution just looking for a problem. How long has FIU been in that location? One pedestrian was struck and killed so you spend 100s of millions to design and construct a bridge using 'innovative' (unproven/untested) design and so you don't detour a few people, you make the unproven/untested/unstable bridge 'portable'. This leads to the death of 6 people, injuries to others, 100s of millions wasted and millions more coming in pending lawsuits and fines. All because a single person either crossed against traffic OR had the right of way, but was dead right.

How much could have been saved, if they simply put a better set of traffic/pedestrian signals? So wasteful.

Well, your 100s of millions for the bridge is off by a factor of ten, but the lawsuits amounts are correct. I'm gonna say that it's more likely it was done because some executive didn't like the long wait times at a light for students to cross the street, more than on one person being killed.

 

[Streetcar]

The bridge was probably a signature gateway for the college and state was planning to widen the road, which would make the road harder to cross and delay vehicles for longer walk light