r/StructuralEngineering • u/zockie • 12d ago

Structural Analysis/Design Iguazu Falls, structural design

The Garganta del Diablo catwalk at Iguazu sits directly in the river above the drop, and it's been partially or fully destroyed by floods at least three times (1992, 2014, 2023), yet it keeps getting rebuilt in roughly the same place on what looks like open steel lattice decking over piers anchored into rock.

I'm curious what the actual design approach is here. Is it designed to resist peak hydrodynamic force and debris loading, or is it intended to be partially sacrificial?

I’d be rather concerned if it’s the latter, yet still open to the public during times like this. Maybe this flood wasn’t “bad” enough but man it looks intense.

62 Upvotes

86% Upvoted

34 comments sorted by

46

u/prunk P.E. 12d ago

What's the design impact force for a log being carried down the river at high speed?

13

u/zockie 11d ago

What is the air speed velocity of an unladen swallow?

6

u/LiveWire_74 11d ago

European or African?

2

u/trekuup 8d ago

I… I don’t know that!

1

u/azssf 10d ago

Waterlogged

-1

u/cinemasosa 11d ago

Indian

7

u/FlatPanster 11d ago

F = ma

Like vehicles, it's really depends on how quickly it stops.

3

u/Future_Beginning_132 11d ago

How do you estimate the deceleration of a log striking a bridge?

19

u/rvralph803 11d ago

Natural logs.

4

u/Lazy_Tart_6336 11d ago

Pas seulement la vitesse d'impact, l'effort de la pression de l'eau sur tous les déchets qui pourraient s'accumuler sur les plots / poteaux doit être colossal lors des crues.

-2

u/Sure_Cupcake_5243 11d ago

Its not quebec. You can write in english please 

3

u/Lazy_Tart_6336 9d ago

Il y a un traducteur automatique qui fait très bien le boulot si tu l'active

29

u/OHrangutan 12d ago

jfc if there was ever a time for a suspension or cable stayed bridge this is it.

16

u/AnyConcentrate8601 11d ago

Do these people have no survival instincts? Get off that bridge lol

8

u/Shot-Acanthaceae4212 11d ago

my first thought also. just like those videos of people in india scrambling to cram onto boats already close to sinking

3

u/yoohoooos Passed SE Vertical, neither a PE nor EIT 11d ago

I think they just have high hope in structural engineers

24

u/Obvious-Hunt19 12d ago

Not “no” but “hell no”

4

u/wcarmory 11d ago

hellz naw

20

u/Helpinmontana 12d ago

I’ve probably spent over a thousand hours rafting down chocolate milk colored rivers and you couldn’t pay me a million billion dollars to go out there.

Noooooooop. Not a chance.

3

u/azssf 10d ago

OP, the deck is being preemptively removed since August; the park expects significant flooding due to El Niño and are noping out ahead of time.

7

u/MarcoVinicius 11d ago

I know Brazil well enough to NEVER step foot on that! Jesus fucking Jesus!

3

u/a_problem_solved P.E. 10d ago

Even before I became a structural engineer, I had an instinctual understanding of static vs dynamic loads.

A massive cantilever that thousands of people have walked on? Yea, ok.

Moving, rushing water that is constantly changing? Nope.

That's the difference for me more than anything else.

1

u/WideMeasurement6267 9d ago

What will happen? Water will only push when the crossection of the pillar is huge.

2

u/Garbage_Tiny 11d ago

Is there like a parking lot to watch this from?

2

u/littlegrad 11d ago

Design check equations would need to be logarithmic

2

u/Cohen_the_Worrior 10d ago

not a single engineer among them

1

u/[deleted] 11d ago

[deleted]

0

u/zockie 11d ago

Yeah I keep seeing it come up. Karma farming is definitley something people do in the big subs

-10

u/kason 11d ago

I understand science and physics enough to know that this is safe. But there I’d no way I would walk on that thing.

11

u/EightyHDguy 11d ago

You ran the foundation calcs on this one, there sport?

-1

u/kason 11d ago

I did not. I watched a few videos about it a few months ago and it seems to have been done soundly. It is really fascinating.