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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)

#131

Post by hinkley »

anamexis wrote: post #96
vharuck wrote: post #78

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 t…

Engineer Guy (Bill Hammack) has a great video about this. https://www.youtube.com/watch?v=hUhisi2FBuw Edit: Just realized this is the same video you referenced. All of his work is fantastic.

I really liked this video when I watched it. I may have watched it twice.

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

#134

Post by kbenson »

tetrep wrote: post #116
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!

> *A straight wall of the approximal strength and length of a wavy wall, not just length. The article suggests that, if you attempted to build a straight wall with a similar amount of bricks, that it would not be able to be freestanding (i.e. it would need to be buttressed or it would fall over). That's a significant feature of a wall to some people, so I don't think it's fair to dismiss the utility of that by sugges…

> so if you need a tall wall, you need more horizontal space for the wave and a wavey wall becomes less ideal.

Not necessarily. You might need a straight wall to be thicker or have more buttressing in that case as well. The requirements for each (waviness, thickness, buttressing) likely change to different degrees based on height, so wavy walls could become less ideal, or they could become more ideal.

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

#135

Post by 3cats-in-a-coat »

rvba wrote: post #130
3cats-in-a-coat wrote: post #113

Earlier quoted context omitted.

Same about waviness on plastic bottles. https://www.riverkeeper.org/wp-content/uploads/2018/04/bottl...

The waviness around makes it easier to hold them too. Although to some degree it might be marketing as well?

It's a combination of structural variation, like with the bricks, and branding. Because as long as it's "waving" it doesn't matter how exactly it waves except in some critical areas, like where you hold it, the bottom and the top.

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

#136

Post by hinkley »

Retric wrote: post #109
DrBazza wrote: post #59

Earlier quoted context omitted.

The 'space wasted' on an estate of many hundreds, if not, thousands of acres is minimal. Given that often the bricks used were made and fired on site, it definitely saved on resources and labour. There's a stately home close to me that has a very short run of one of these walls, and the remains of the old brick kiln up on the hill side. If you know what you're looking for, you can also still see the hollows in the gr…

It cost even less labor to use minimal bracing for strait walls, these are curved for athletics. I suspect they are imitations of curved fruit walls popular in the 1600’s before greenhouses took off.

> these are curved for athletics.

Autocorrect strikes again.

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

#137

Post by travisgriggs »

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!

Amen to this. In a tabloidish sense.

I read the title and thought "duh". Maybe others were intrigued and clicked, but for me, this is just obvious. I had lots of legos, and own more now as a grandpa than, er, uh, I should. I guess spatial reasoning about bricks just is second hand at this point.

What the article likely leaves out, is that the all of the "corner only" touch points are going to create a more "pourous" wall. And collection points for crap.

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

#138

Post by mcpackieh »

anamexis wrote: post #96
vharuck wrote: post #78

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 t…

Engineer Guy (Bill Hammack) has a great video about this. https://www.youtube.com/watch?v=hUhisi2FBuw Edit: Just realized this is the same video you referenced. All of his work is fantastic.

I've encountered a few of his videos on wikipedia (creative commons license.) Pretty neat.

His 'drinking bird' video is used on the wikipedia page for the same: https://en.wikipedia.org/wiki/Drinking_bird#Physical_and_che...

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

#140

Post by hinkley »

contravariant wrote: post #85
tonmoy wrote: post #79

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 pi L/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 2 L/l number of bricks which is fewer than the wavy walls

Semicircles seem excessive. At no point does the wall have an angle over 45 degrees, so a semi-circle which would be at a 90 degree angle for every inflection point seems way too wavy. A sine wave is probably closer, which would give an arc length of sqrt(1+cos(2pix/L)^2). This has no reasonable closed form I can find but it seems like it would be about 21% longer than a straight line. Edit: Also a semicircle is pi/2…

Sines are about 1/.7 (40%) longer aren’t they?
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