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FIU had grand plans for 'signature' bridge. But the design had a key mistake

miamiherald.com

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Re: FIU had grand plans for 'signature' bridge. But the design had a key mistake

#111

Post by seszett »

function_seven wrote: post #110
crwalker wrote: post #44

Earlier quoted context omitted.

Yes! Good thing you pushed back on the architect. I have a similar design philosophy that honesty is more aesthetically pleasing than deception. When designers resort to faux materials and structures, the truth still tends to peek through, resulting in an 'uncanny valley' of forms. For example: * Brickwork veneers bend in the wrong spots * Faux beams are placed in the wrong locations with the wrong joints, announcing…

The worst example of this are those faux shutters that seem to outnumber real ones. They're rarely wide enough to actually cover the adjacent window! https://imgur.com/a/o9Nxx6c EDIT: Added examples of fake garage door handles and hinges. I'm seeing that a lot more and don't understand the point.

Wow, I had never seen this but that's impressive, I didn't even think this kind of thing could exist.

Re: FIU had grand plans for 'signature' bridge. But the design had a key mistake

#112

Post by jacobolus »

ScottBurson wrote: post #69
danso wrote: post #2

Saw this story via an @EdwardTufte tweet: https://twitter.com/EdwardTufte/status/1007395311541682176 > A+ This is beautifully executed technical report by the Miami Herald, an instant classic of news reporting. Note that this report is a document not a deck. The FIU admistration loaded the bridge design down with features.

Wow, I thought it seriously needed an editor to take an axe to it. I usually like long pieces, but this just seemed repetitive.

The way newspaper articles work, not every reader is expected to read the whole thing.

They are structured to put critical information up front, so that a reader can stop whenever they lose interest without missing anything more important than what they already read, but include additional detail below for those who are more deeply interested.

This leads to the same main points being repeated several times, which can be a jarring style for readers who are not used to reading newspapers. Long magazine articles are typically structured quite differently.

Re: FIU had grand plans for 'signature' bridge. But the design had a key mistake

#113

Post by burfog »

gamblor956 wrote: post #104
tropo wrote: post #89

Earlier quoted context omitted.

The stays were real. They were needed for hurricanes and large crowds. The worst case would be a marching parade, on just one side, during a hurricane.

No, the article is pretty clear that the stays were fake, and intended solely to dampen vibrations. They provided no structural support whatsoever.

If it is "to dampen vibrations" then obviously it isn't "fake". Vibrations are serious business; many bridges have collapsed due to vibrations, and many more (Millennium Bridge for example) have had severe trouble. Humans are particularly prone to causing vibrations because humans react to bridge movement in a way that amplifies the movement.

Technical description of the bridge from the engineering firm:

https://facilities.fiu.edu/projects/BT_904/MCM_FIGG_Proposal...

Page 3: "The stay cable pipes increase stiffness for pedestrian loads."

Page 18: "The stays and pylon provide the required structural design to meet the pedestrian loads for harmonic conditions of natural frequencies"

Page 64: "HORIZONTAL FREQUENCY In the lateral direction, the fundamental frequency of the pedestrian bridge shall be greater than 1.3 hertz. VERTICAL FREQUENCY The fundamental frequency in a vertical mode shall be greater than 3.0 hertz to avoid the first harmonic."

Page 65: "The pylon stiffness was designed to provide significant benefit to the overall stiffness of the structure."

Re: FIU had grand plans for 'signature' bridge. But the design had a key mistake

#115

Post by pseingatl »

ebikelaw wrote: post #15

The article barely touches on the subject, but the bridge was really unnecessary, or necessitated only by the nonsensical urban design surrounding the university. The student housing is not only on the opposite side of a gigantic road from the campus, but it's further separated by a canal and then acre after acre of parking. If any attention had been paid, at all, ever, to the built environment this bridge would not…

The community was there before the university. It wasn't that long ago that it was Tamiami Airport, which has now moved even further west.

Re: FIU had grand plans for 'signature' bridge. But the design had a key mistake

#116

Post by pseingatl »

PebblesRox wrote: post #73
JohnJamesRambo wrote: post #27

Earlier quoted context omitted.

“Hey guys let’s go hang out on the bridge over the highway.” It is like a plaza, but a bridge! Ignore the fumes and deafening roar of traffic.

A successful example of this is the I-670 cap bridge in Columbus, OH. The bridge is lined with buildings so it’s hard to tell you’re even on a bridge. It has the advantage of being over a sunken highway, so there’s no grade change to deal with. https://www.google.com/search?q=the+cap+at+union+station&lr=... :

Or the Rialto.

Re: FIU had grand plans for 'signature' bridge. But the design had a key mistake

#118

Post by kilotaras »

cagenut wrote: post #6

This is a really good article. Amazing how a dozen+ different things combined to produce the unfortunate result. Perfect case study in there being no such thing as a singular 'root cause'.

> Amazing how a dozen+ different things combined to produce the unfortunate result.

That is to be expected. Real world projects are usually resilient enough, that only when a lot of things align catastrophic failure happens, AKA Swiss Cheese model [1]

[1] https://en.wikipedia.org/wiki/Swiss_cheese_model

Re: FIU had grand plans for 'signature' bridge. But the design had a key mistake

#119

Post by oldcynic »

angersock wrote: post #92
elefanten wrote: post #77

Earlier quoted context omitted.

Can you elaborate? This seems like a very perverse system. Why is criticism viewed to be so dangerous? As long as both the critic and the criticized are supporting their arguments with reasons and engaged in dialogue, the outcome should be net good for everyone.

> Why is criticism viewed to be so dangerous? Criticism, behind closed doors or strictly in the company of other engineers with the correct training and experience, is not dangerous. Criticism shared with non-engineers amounts to second-guessing and degrades the trust of the public in the profession as a whole, which has tangible negative outcomes for everyone. Imagine if every project you'd been on had another devel…

> Criticism shared with non-engineers amounts to second-guessing and degrades the trust of the public in the profession as a whole, which has tangible negative outcomes for everyone.

Also makes it ever so easy to bury the negligence and mistakes. Leaving the public devoid of trust and potentially with some very tangible negative outcomes. For instance:

"Yes your condition should have been identified, it's clear from the first X-rays in your history. No it's too late to do anything about it now, you just have to live with it. Put that in writing? I couldn't possibly do that."

Repeat several times.

Applicable to many of the professions in varying degree.

Re: FIU had grand plans for 'signature' bridge. But the design had a key mistake

#120

Post by workinthehead »

function_seven wrote: post #110
crwalker wrote: post #44

Earlier quoted context omitted.

Yes! Good thing you pushed back on the architect. I have a similar design philosophy that honesty is more aesthetically pleasing than deception. When designers resort to faux materials and structures, the truth still tends to peek through, resulting in an 'uncanny valley' of forms. For example: * Brickwork veneers bend in the wrong spots * Faux beams are placed in the wrong locations with the wrong joints, announcing…

The worst example of this are those faux shutters that seem to outnumber real ones. They're rarely wide enough to actually cover the adjacent window! https://imgur.com/a/o9Nxx6c EDIT: Added examples of fake garage door handles and hinges. I'm seeing that a lot more and don't understand the point.

The brick house with the faux shutters is also using faux lintels -- the bricks are vertical but since there is no overlap and no arch they are providing no structural support.
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