Posted on 03/15/2018 11:32:16 AM PDT by Red Badger
MIAMI (CBSMiami) — Florida International University’s massive new pedestrian bridge collapsed Thursday afternoon in West Miami-Dade.
The bridge, located at 109th Ave and 8th Street, collapsed on a number of cars.
There are reports of numerous people injured in the collapse. At least one person was taken as a trauma alert to the hospital, according to Miami-Dade Fire Rescue.
The 950-ton bridge went up on Saturday. It was then lowered into its final position, just west of 109th Avenue that day.
The main span was built next to Southwest 8th Street.
Or GA Techs?
5.56mm
First thing that occurred to me was to wonder if the designers were aware that the highest load that you can put on any bridge is wall to wall people. since people never got to use it, it's a moot point. But if...
The Golden Gate Bridge 50th Anniversary with wall to wall people its entire length (300,000+ people) Is a classic example of the massive weight.
There is an iconic color photo that appeared at the time which I think might be on a poster too, but I have never be able find one to buy a copy. The bridge looks flat between the towers from the weight.
I can't help wondering if there was pressure at work from wherever to prevent public distribution of that image.
FIGG has had a bridge collapse before!! And they were fined.
Back around that same time my Dad, an engineer and an architect, told me the same thing. On bridges and such they always designed in a safety factor of five.
But they don't do any good if you sleep through the classes.
As several people have pointed out, this is a suspension span ... with no suspension. A detail not safely overlooked.
From Hammurabi's Code to the present in a nutshell.
The octopus has tentacles.
The I-35 bridge in Minnesota collapsed in 2007 (original design flaw (which held up for 40 years though)); a new pedestrian walkway within the Kansas City Hyatt collapsed on its first evening of use in 1981 (construction mistake). Those are the ones that come to mind immediately.
https://en.wikipedia.org/wiki/I-35W_Mississippi_River_bridge
https://en.wikipedia.org/wiki/Hyatt_Regency_walkway_collapse
An excellent book. I've read it in its entirety at least three or four times over the years.
Four months, and obvious problems on Day One: https://en.wikipedia.org/wiki/Tacoma_Narrows_Bridge_(1940)
Right link: https://facilities.fiu.edu/projects/BT_904/FIU-Pedestrian-Bridge-Design-Criteria-2015-05-06_REV.pdf
I think this was the bridge used by thousands of kids as they marched out of school for that gun violence day thing. (J/K)
10,000 fat people :-)
I’m pretty sure the diagonal structures are just to make the bridge look cool. “Hey - we’re already over budget - lets get rid of that artsy stuff!”
I can’t imagine all the people involved that missed the critical features. Here in Seattle they had to tear down a 12 year old, 14-story building because someone didn’t dab epoxy on the ends of some steel cables - they started rusting through.
So the worker didn’t do his job, his manager didn’t, the company inspector, and the city inspector. (I might be missing someone.).
And I'm pretty sure one of our engineers will be along shortly to disabuse you of that notion ;-)
If there was any cosmetics involved, it might have been some type of decorative cladding on the cable stays.
There was to be two spans of that 'bridge', one over the road and the other shorter half over the canal next door.
The supporting pylon was to sit in a grassy area between the two, with the cable supporting both halves.
Not cosmetic at all, but - very obviously - absolutely necessarily, structurally.
See pic in #477 above
I coukdnt get thru the first paragraph before dropping my jaw.
My first thought was substandard Chinese steel. I once heard an interview with someone at a large construction firm who talked about how the Chinese manipulated steel testing results. But it sounds like there are a lot of other potential causes.
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