Thank you for explaining this elegant design. You are an excellent teacher.

In my highschool engineering class we built a bridge about 3 feet long. We weren't limited on resources. So my group decided to just throw a bunch of sticks (not literal sticks) and shape it into the form of a bridge and then just cover the entire thing in hot glue. The teacher said confidently that our group will most likely get last place. News Flash and to everyone's shock in the classroom we were first place. I didn't like that teacher anything an upperclassman did I was blamed for it.

You won me over, I thought this would be a video explaining to me that I just shouldn't be an engineer. Whether it is economically advisable or not I like engineering things too much. By the end of the video though, I have a new appreciation for AI

I've wondered for years why the bases of large electrical towers, cell phone towers, etc. are so small at the bottom. It all makes sense now.

Hey Paul, I am a sculptor and would love to connect with you. What would be the best way. Thank you . Kal

Tanks

these structures were used thousands of years ago by Polynesian sailing ships, thy used construction with tension and compression elements to support the hull, these are lighter than carbon fiber hype just as simple cotton fabric on frame dinghies are too. This knowledge should spread to build community public works and dissolve all genocide billionaires dictatorships still called consumer "democracies"

Excellent and understandable; thank you.

This test seems somewhat unfair because the failure mode for most of the bridges depends less on their load bearing than how well the participants can center their weights. Can someone explain why the balancing aspect was so important that they couldn't just clamp down the ends so the weight placement was less critical?

Why that disturbing music ?

Yes now a days the shaft of the big pumps is not a heavy rod but a wider hallow pipe . When the motor is two floor upper than the pump

Wow. I have a MS Structural Engineering from UC Berkeley. We had to use toothpicks. Public university.

Could you explain better why the forces go upwards? I watched your other video on domes and didn't understand it. Do they go upwards towards the oculus because the dome is collapsing inward so to speak? I can't get my head around why forces go up and gravity pulls things down.

I'm still reeling from a much-better-than-it-has-any-right-to-be Mitch Hedberg impression.

Cool cool cool cool I love it Magical I hope i can visit it one day Thank you for your videos

Isn't spaghetti a bit like concrete? (non-reinforced concrete with ridiculously high slenderness ratio?)

Any thoughts on 3d printed cob/clay such as in the wasp project? It looks like a good eco-friendly construction technique

Interesting video to see college students bridge contest. My daughters' high school physic teacher 25 years ago ran smaller scale bridge contest. Balsa, glue and string for materials, bridge had to span 3 feet and be able to roll a 2 inch steel ball along its length. Winner was load vs. bridge weight. I am a retire engineer and substituted at the school so always went to watch the testing.

Kind of funny to imagine this testing methodology scaled up to real-world bridges - a massive 500 ton weight plopped right in the center of the golden gate bridge

Would you say the first bridge failed due to lateral torsional buckling?

Concrete, including Roman concrete, is always a chemical reaction and does not "set" with exposure to air. Why did she say that?

SO what bridges won each class? What was the load on the last one #13?

Bridge #4 looks awful

Obviously none of them have studied the art of "Armadillo run" (pc game). Seriously though, cool ideas

It's good to remember that if you pull your belt too tight, you'll suffer from buckling. Nice work all around.

I love this video, I think teachers like Paul Kassabian are truly inspiring for students. My only observation about this is I believe the testing method is flawed. Every team placed and added the weights in different way, this creates different loads (i.e torsional) with different centers of mass. This caused some bridges to twist before there was a material collapse. I suggest using an standardized load plate where you can add more mass in equal way.

@realcivilengineergaming maybe this will give you a relaxing break from balatro.

I really enjoy how you explain things hopefully one day we will be allowed to make spherical dream catchers of any size I believe a spherical dreamcatcher can be made 100 km high because it only uses rings and wire to put the structure together and because of the fact that it only uses rings and wire it is capable of achieving any size and hopefully we will be allowed to discuss making a spherical dreamcatcher which is 100 km high

that one at 10:30 , you should mention those upper cables dony actually do anything, you should fail them. Surprised you didn't mention it

Today, I learnt that a 2x4 is stronger than even the most intricate of bridges. I’m an engineer now.

The weights used to apply the experimental loads were problematic.

Happy to see Harvard educate rather than indoctrinate.

Most loads are too top heavy causing more torsional twist.

To tension cables on a model bridge using a similar system to that of a guirar in which you wrap one end around something you can twist to wind them up is what I find works best. You can adjust the tension of different cables even after you start loading weight.

We did this in highschool with 50 tongue depressors over 16". Over 25yrs ago.

Ah, I think that last one was like the Troy-Menands Bridge.

Excellent Project !!

I like this video because as venetans (from the region of Venice) we only think about the controversies of this bridge, while you highlighted the finer and artistic details. I still think it was a huge waste of money, it is dysfunctional because of the glass and inaccessible for the disabled, badly designed, but i learnt something new!

As an architecture student I sometimes have to force myself to watch engineering videos to be able to understand buildings better, however I find your videos very understandable, useful, and helpful

Great work, explained in a simple way. That's what our students need.

best videos about Behavior of structures

very beautiful

Thank you so much for creating and sharing such a useful and engaging video! Despite the many issues this pedestrian bridge faces, its structure is extremely interesting and inspirational. The concrete entrance of the bridge is elegantly shaped and harmoniously integrated with the steel components that make up the main structure. The steel deck is structurally complex, which I believe adds to its uniqueness. I think that wearing a pair of skates in the winter would make it more enjoyable! 😊

He is mixing "business" with pleasure... ✔

Damn graffiti on the glass... BTW, it would've been nicer a little bit of attention more to the finishing of the steel works. I mean the welding marks. Also, color scheme of red isn't that nice.

Thanks

3:54 I wanted to see the result of this. A catenary vault, there are some incredible parametric examples of this done with units that seem to be halfway between a tile and a brick 😄

Beautiful bridge. The varying risers reminds me of Scarpa’s bridge in Venice. There seems to be a lot of streaking on the bridge, looks like there’s a bit of a rain water management issue. What do you think is the cause?

You have to try those steps in autumn/winter on a foggy day or a rainy day. :D The glass part becomes extremely dangerous because it is very slippery, and everyone is forced to walk on the little part in stone!

Lovely video on a beautiful work of art. What is the finish of those slippery steps? Looks like a smooth tile.?. I wonder if there is a way to address that without replacing everything.