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Wavy walls use fewer bricks than a straight wall (2020)

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Re: Wavy walls use fewer bricks than a straight wall (2020)

#71

Post by tomxor »

geeky4qwerty wrote: post #26

This feels a bit like diet clickbait... "use fewer bricks than a straight wall"* *A straight wall of the approximal strength and length of a wavy wall, not just length. My counter would be that from a practical perspective the amount of space wasted by the wavy design seems to negate the usefulness of the design. Probably makes the lawn crew dizzy when mowing it too!

Walls have purpose beyond neatly cut lawns.

This wall would work well at road field boundaries where a couple feet makes less practical difference than the large saving in materials.

Re: Wavy walls use fewer bricks than a straight wall (2020)

#72

Post by etskinner »

pfdietz wrote: post #66

The labor to build such a wall may dominate the savings in brick. But if you're building a brick wall, maybe you don't care much about either. I wonder if this sort of structure could be built by 3D printing, say with concrete or even soil.

There's actually a similar concept in 3D printing called gyroid infill, it's essentially a 3D version of the wavy wall:

https://www.wevolver.com/article/understanding-the-gyroid-in...

Re: Wavy walls use fewer bricks than a straight wall (2020)

#73

Post by bee_rider »

turnsout wrote: post #43
geeky4qwerty wrote: post #36

Earlier quoted context omitted.

Good point. I'd say if you're tight on money I'm not sure a wall should be at the top of your to-buy list.

It is if you're selling sheep milk and you don't want to lose your flock.

I think that’s typically a job for fences, right?

This sort of wall is, I think, just an aesthetic way of marking a property line/get some privacy.

Re: Wavy walls use fewer bricks than a straight wall (2020)

#74

Post by toss1 »

Very cool. So what is the optimal solution?

To maximize the strength and minimize the bricks used, is a sine the best shape, or is there a better curve, and what is the best period and amplitude of the waveform? Does this solution change with the height of the wall?

Re: Wavy walls use fewer bricks than a straight wall (2020)

#75

Post by jacquesm »

hammock wrote: post #61
vehemenz wrote: post #45

Earlier quoted context omitted.

The extra space doesn't have to be fully wasted. You could plant bushes or small trees in the concave sections.

Applies to flat walls not wavy, but espalier,[1] a way to cultivate trees in tight spaces, is one of my favorite things ever. [1] https://en.wikipedia.org/wiki/Espalier

I'm doing this with an apple tree right now :)

Re: Wavy walls use fewer bricks than a straight wall (2020)

#76

Post by jwilk »

paiute wrote: post #60
alecst wrote: post #53

> As for the mathematics behind these serpentine walls and why the waves make them more resistant to horizontal forces like wind vs straight walls, check out this post by John D. Cook. The linked post does not explain why the walls are more resistant to forces. It just calculates the difference in length.

https://www.johndcook.com/blog/2019/11/19/crinkle-crankle-ca...

That's the same post that is linked from the original article.

Re: Wavy walls use fewer bricks than a straight wall (2020)

#77

Post by Cerium »

nonethewiser wrote: post #64

I see this a lot in the rural US with wooden fences but had no idea why it was done, but I guess its for the same reason (stability). Apparently they've done it since the 1600s. https://www.louispage.com/blog/bid/11160/worm-fence-what-is-... Still, this seemed totally unecessary until I realized this mean they dont have to put any posts into the ground. No digging holes, which would be really nice when you're trying…

Those fences are also popular in places where it is cold in the winter. No posts in the ground means no frost heave. A fence like that can sit unmaintained for decades before it starts to fall apart.

Re: Wavy walls use fewer bricks than a straight wall (2020)

#78

Post by vharuck »

Soda cans also have a counterintuitive efficiency feature: concave bottoms. If a can with a flat bottom held the same amount of soda, it would be shorter and have less surface area, but its metal body would need to be thicker to withstand the same pressure. In the end, it'd require more aluminum.

https://www.csmonitor.com/Science/Science-Notebook/2015/0414...

^Probably not the best article for this, but it was easy to find and has a link to a chemical engineer's video.

Re: Wavy walls use fewer bricks than a straight wall (2020)

#79

Post by tonmoy »

Not sure about the actual function that defines the wave, but let’s assume they are convex and concave semi circles. Then to make a wall of length L with bricks of l length, we need piL/l number of bricks. The linked Reddit post says a straight wall needs to be 2 bricks wide to have the same length, which needs 2L/l number of bricks which is fewer than the wavy walls

Re: Wavy walls use fewer bricks than a straight wall (2020)

#80

Post by asimpletune »

toss1 wrote: post #74

Very cool. So what is the optimal solution? To maximize the strength and minimize the bricks used, is a sine the best shape, or is there a better curve, and what is the best period and amplitude of the waveform? Does this solution change with the height of the wall?

Most likely you want the smallest curve that’s achieves an acceptable amount of stability. Since the wave exists to prevent the wall from toppling, a pure sine is probably overkill.

So I guess a factor then will be how tall your wall is. A very tall wall will need a deep wave, just like a wall one brick high would need no wave at all.

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