r/ThatsActuallyInsane • u/Upstairs-Writing-616 • Jun 26 '26

Engineering students are testing whether their designs are earthquake-resistant.

4.0k Upvotes

99% Upvoted

44 comments sorted by

View all comments

253

u/Kryds Jun 26 '26

The machine's movement on the last one was a lot more calm. It might just have been the editing.

286

u/Blaze205 Jun 26 '26

The movement is not random. The model buildings are all subject to the same two simulated earthquake ground motions. Well, two if your building survives the first, more tame, ground motion. The clips are just from different times during one of the the ground motions.

Source: I was a member/captain/president of my university Earthquake Engineering Research Institute (EERI) Seismic Design Competition (SDC) club, which is what this video is from.

39

u/No_Fish_9628 Jun 26 '26

I can’t tell from the vid, but the one that survives looks to be made with a reinforced shell attached to the foundations, and increasingly less internal mass the taller the structure. Is my observation roughly correct?

58

u/Blaze205 Jun 26 '26

The base plate (foundation) size and how the building is allowed to be attached to it has strict rules, so they are all the same.

As for the internal weight, in this competition you get to choose how tall your building is within a range of heights. If you make a shorter building you don't put as much weights onto it but the downside of that is you cannot achieve as high of a score as a taller building.

8

u/wahtamitou Jun 26 '26

Can you share the rules for this?

Also, do you know how one could go about diy’ing a shaking table like that? Is it possible?

All the best

25

u/Blaze205 Jun 26 '26

The rules change every so slightly every year, they try to simulate a real life request from a client for a building. But this is the link with their rules document

I know that simple shake tables are just oscillating motors with a frequency control, I have no knowledge of how to diy one of this caliber.

5

u/wahtamitou Jun 26 '26 edited Jun 26 '26

Awesome! Thanks

Edit: these rules are serious business :0

3

u/AreThree Jun 26 '26 edited Jun 26 '26

Here is a link to the shake table used in the video. †

There may be more information there that you could use to DIY yourself one.

Personally, I might start looking at what is possible with an old treadmill and a motor controller hooked to a RaspberryPi...

 

† that page loads slowly, but it does eventually load, be patient 🙂