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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

#101

Post by echotango »

mannykannot wrote: post #67
echotango wrote: post #59

Earlier quoted context omitted.

I agree with you, but only because you seem to have missed the crux (no irony intended) of Ayn Rand's ideology. She hated how even the style of the buildings around her embodied a people and culture she saw as a threat to her vision of the world and wanted to tear down. She would have no "homage" to it at all.

We are under no obligation to regard Rand as the last word on anything, fortunately.

Agreed. It's pretty questionable to tell a Frenchman he shouldn't be proud of the Eiffel Tower because he didnt personally design it.

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

#102

Post by echotango »

paulie_a wrote: post #75
echotango wrote: post #50

Earlier quoted context omitted.

I agree, it is beautiful. But Ayn Rand would have hated it. That design is steeped in European and Christian traditions and symbolism. Those things are all anathema to her ideology.

But honestly who gives a shit about what Ayn Rand would have thought about it. She was a nut and her ideology should be aggressively dismissed as simplistic and quite frankly stupid.

I totally agree. I was pointing out that church isn't really modern architechture as Rand saw it.

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

#103

Post by yorwba »

echotango wrote: post #101
mannykannot wrote: post #67

Earlier quoted context omitted.

We are under no obligation to regard Rand as the last word on anything, fortunately.

Agreed. It's pretty questionable to tell a Frenchman he shouldn't be proud of the Eiffel Tower because he didnt personally design it.

Then why do you keep bringing up Rand's opinion on architecture only to state that you disagree?

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

#104

Post by gamblor956 »

tropo wrote: post #89
hrunt wrote: post #40

Earlier quoted context omitted.

It specifically was NOT a cable-stayed bridge. It was a non-redundant truss bridge with a tower and faux stays that contributed nothing to the structural capabilities of the bridge. The arrangement of the truss structure mimiced the stay angles purely for aesthetics, not for any other reason. The choice to use a single truss structure rather than a more traditional redundant set of trusses was due to the desire for a…

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.

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

#105

Post by angersock »

tankerslay wrote: post #99
angersock wrote: post #92

Earlier quoted context omitted.

> 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…

"Scandal" should be avoided because it "degrades the trust of the public in the profession." An age-old saw trotted out to justify the cover-up of diverse kinds of negligence and malfeasance in all manner of professions the world over. It works precisely until there is a scandal too big to cover-up.

There are always degrees of uncertainty in any physical engineering project. It doesn't help anybody to have the general public being told to second-guess the work.

Why do you think otherwise?

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

#106

Post by angersock »

abduhl wrote: post #96
bsder wrote: post #71

Earlier quoted context omitted.

> It bugs me that FIGG (one of the contractors) appears to be threatening the professional licenses of the engineers who helped the Miami Herald's investigation, by suggesting that doing so was unethical. As a licensed Professional Engineer, you have to be quite careful criticizing other engineers. As long as the engineer signing off met "standard practices", he is covered and saying that he is not could get you in q…

I'm unaware of any liability that can be picked up through rendering an opinion on a design. I have participated in forensic engineering / expert witness cases in geostructural matters. In fact, the opinion of an engineer as an "expert witness" is often codified in law as retaining no liability. Asking questions and drawing conclusions is not something that presents any risks besides you being possibly proven wrong l…

Acting as an expert witness and sounding off unbidden are somewhat different.

It's also not so much a matter of law as it is professionalism.

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

#107

Post by my_username_is_ »

WalterBright wrote: post #86
Mtinie wrote: post #45

Earlier quoted context omitted.

Static force analysis only works when the materials being modeled are well known. Titanium dioxide concrete is a novel material—and, from the article’s text and subsequent research—appears to have a narrow effective range before integrity issues appear.

Knowing the strength of materials is pretty darn basic.

I would disagree. System failure modes can be quite complex. Yes you may have a good approximation of a material's Ultimate Tensile Strength through lab testing (although it isn't a single number and can be affected by a lot of variables, so it's usually designated as a range). But if your material yielded in a way that didn't account for, it could affect the loading on a different member, and trigger an issue with an entirely different part. Real world systems are more complex than your freshman year Statics assignments

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

#108

Post by WalterBright »

my_username_is_ wrote: post #107
WalterBright wrote: post #86

Earlier quoted context omitted.

Knowing the strength of materials is pretty darn basic.

I would disagree. System failure modes can be quite complex. Yes you may have a good approximation of a material's Ultimate Tensile Strength through lab testing (although it isn't a single number and can be affected by a lot of variables, so it's usually designated as a range). But if your material yielded in a way that didn't account for, it could affect the loading on a different member, and trigger an issue with a…

Actually, I worked for Boeing on gearbox design. So I am fairly aware of strength of materials and did a lot of such computations. If you're unsure of the strength, you use the minimum guaranteed value. You don't use materials for critical pieces for which you don't have any data. That would be incredible incompetence.

Again, what I am talking about is using statics to determine the minimum loadings to check against the computer models, which should predict higher values or they are wrong.

This is not difficult.

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

#109

Post by Animats »

A real cable-stayed pedestrian bridge, one that's both longer and cheaper, is in Cupertino, CA, crossing I-280.[1] That was done without major disruption to I-280 traffic. There were some lane closures and two or three late night closures for a few hours.

FIU built a fake one that was more expensive than a real one.

[1] https://en.wikipedia.org/wiki/Don_Burnett_Bicycle-Pedestrian...

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

#110

Post by function_seven »

crwalker wrote: post #44
beachy wrote: post #3

> But FIU's bridge was designed to mimic the dramatic look of a cable-stayed bridge, where the deck is suspended from cables fanning out from a tall mast. In FIGG's design, though, the "cables" — actually metal pipes — were mostly just for show. The diagonal, v-shaped struts of the truss did the structural work. I've always found it useful to hone in on anything that is done purely for aesthetic reasons. We build a h…

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.

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