How putting the arch back in architecture could save the environment | Matthias Rippmann | TEDxBasel

So who likes doing laundry? No one really likes doing laundry and I don't either, but at least it can give me a little inspiration because every time I hang my socks and underwear on a clothesline I get to see some really cool clothes. design for a new structure I know it sounds a little strange because a clothesline is usually a good way to dry clothes, but you can also look at it differently because the hanging shape of a clothesline, its inverted shape forms the perfect

arch

and compression. and

arch

ers in

architecture

are super efficient structures, so let's design one, let's take your clothesline or any flexible rope or hanging chain and yet you hang it between two points, you trace this shape and then you just turn it around and that's it, it is perfect.

The compression bow and archers are super efficient structures because they use the material effectively and only where they really need it, but of course this principle is not new, it has been known for hundreds of years and people built amazing structures using This principle is still valid today. compression and forming a perfect arch and when I looked at this structure for the first time, it is amazing Kings College fan walls, I thought it is incredibly beautiful, but at the same time I also thought that this stone roof must be incredibly massive and heavy. Well, actually, it's not because what you see, the stone structure is proportionally as thin as a real stone, isn't it amazing that you can build stones in space? that this man was also inspired by these structures.

His name is Heinz Easler, an incredible Swiss engineer and I don't know if he himself was hanging his clothes on the line, but I know he was hanging wet sheets on very cold days. in his garden in Switzerland and then he waited for them to freeze so he

could

turn them over and then he looked at these shapes and discovered new shapes for the buildings that he built all over Switzerland. Has he ever passed this gas station on his way? for Bern exactly that was a simulation that sounds easier in the 60s and you look at it and immediately understand it, it looks like an eggshell, it is incredibly thin, so using a hanging form instead of a compressed word is a way really efficient to save. materials and working with materials effectively, but that is not the only aspect that interests me because the structures that I am showing you are also really exciting to me and these shapes are unique, so I want to explore more, but today I don't need to tend my clothes on a clothesline or I need to build complicated models with wet sheets and chains.

In fact, I can use computers and software and explore and discover thousands of shapes interactively in a short time and we at ETH Zurich block research group do exactly that. We develop tools to then design and build novel shapes and sometimes this research also involves building a small hobbit house and this is what we did in the forest at ETH and then we wanted to know how strong this structure really is so we did this . We put some weight on it, so we put 3.5 tons of sandbags on top of it and then we were waiting to see what was going to happen and what happened, well, absolutely nothing, we

could

n't see any cracks, we couldn't measure any deformation because , although we were only using simple bricks, the good structural geometry made this structure incredibly strong, so to continue with our tests we needed to then move on to slightly more drastic measures and this is what we did, it was fun and really brings us good memories, but you don't stop there, you want to fully extend and push the limits of this idea, so we built an extreme stone wall that stretches for 60 meters in the middle, it's only five centimeters thick and it's extreme because what you're watching it's basically a 3D puzzle of 399 limestone blocks balanced in space in compression following a good shape but there's no glue there's no mortar there's no connection between these stones it's basically just one stone pressing against the other and I loved working on that project because to me it shows the concept of good structural geometry in a truly elegant way and through this demonstrator and its elegance.

It is my hope that we can also inspire others, but for this inspiration to also become a source for future actions, we need to share our methods. Purpose is an idea if no one else can access it, so make it accessible and for capable people and this is what we do in our research: we develop tools, but then we also share them freely with architects, engineers and designers so they can build their own. structures when we released the tool freely it's called Rhino Walls a few years ago it started with a few projects here and there and then it really blossomed around the world and it was inspiring to see how people took that idea and took it further and we've developed all these interesting structures and even real buildings, but the question still remains: where can you really make a difference?

Because we don't see these structures very often. What we see in construction are these massive developments that arise all over the world because we need them, we are growing, but the number of these developments is not the central problem, the problem is the material we use to build them, to give you an example, For all new construction jobs in the world, we consume approximately nine billion tons of concrete each. year 9 billion tons, so what does this mean? It is an incredibly high number. I give you an example: they would use all this concrete and we would build a 20 centimeter thick wall with all this material and this wall would extend its entire length.

At the equator, this wall would be 500 meters high, a 500 meter high wall that would stretch around the world and we build it every year. It's a lot of material and we should do something about it, so why not start using material where you really need it? So why not replace, for example, these huge floors that consume so much concrete and steel with something lighter and more efficient? So why not replace them with a bow? An arch and I submerged a floor and this is what we developed, the white prototype that you see in the middle. and it looks better that it contains an arch if we open it and the good thing is that it consumes 70% less material if we compare it with a conventional floor and even if we compare it with floors with a hollow core so that is a big impact, but the prototype that I'm showing you doesn't even contain concrete, in fact, it's made of sand or, more specifically, 3D printed sand, and 3D printing is great for many reasons, but for us the most important one is that we can now add material exactly where we need it and this is something that is impossible using traditional concrete casting techniques, so now we can print complex structures layer by layer simply using sand, a binder and this machine, and this additional complexity does not come with additional costs.

This is a sample piece of this material, 3D printed sand, so it's basically sand glued together, so it doesn't sound very loud. In fact, I can't compress it, I could even stand on it easily, but as soon as I bend it, you'll see. Look, it breaks as easily as a bar of dark chocolate, so it's a really weak material, so it's a little scary, sand stuck together and you're supposed to stand on it, that's right and the good news is that it can take plenty In fact, a load may require half our team or about a ton of nerds and it might even require twice as many nerds and it's just sand you're standing on, so good structural geometry and an arc allows you to work with weak materials. and that opens up opportunities in the way we build today, but this is not only applicable to a high-tech context like here in Switzerland, where all this technology is available, but its principle is also applicable in a low-tech context where these technologies are not available and where sometimes there was not even concrete or steel available, so when we worked on a project in Africa we looked for resources that were easily available and those were local natural materials and local labor, so we took these pressed tiles of soy, an extremely weak material, and then, together with the locals, we build a floor system.

It is simple following an arc, so if two floor ideas use two different material systems in two totally different contexts but follow the same principle Where do we go from here? I don't pretend to know the answer, but I do. where we started, so we start with a simple arc, this simple almost forgotten idea and then we take this idea and take it to the future to combine it with modern tools and technology, so through this we are combining the past with the future and Through From the studies, projects and prototypes I showed, I am hopeful that we can instigate a shift towards less wasteful, more appropriate and also more exciting ways of building today with a little help from geometry and washout along the way. thank you