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A Building Material 12 Times Stronger Than Steel
nm1m writes: "For the last few months I have been following with some interest a few stories (story link may not work) in the school newspaper about a new structural technology being developed at BYU. It is called PYRAmatrix, and is 12 times stronger than steel, yet less than 10 percent the weight of steel. A 47 foot cylinder of this stuff, 16 inches in diameter and weighing just 47 pounds, can support almost 4 tons. It seems to have obvious applications in aerospace, electricity utility poles, radar and communication towers, and just about any structure that needs exceptional strength. An interesting press release with facts and figures can be found here. Photos can be found here." The link worked for me -- and reminded me of the plastic-walking scene in Sabrina .
Every Silver lining has a cloud, and I am wondering about the amount to time that this material lasts. It's fine for it to be a super light polymer, and have the stringth of Cowboy Neal, but how long will it be before it starts to lose it's stringth? How long before it would crack like Jon Katz?
I would hate to live near a power pole made of this stuff, after it had been up for a couple of years.
To my untrained eye it seems like they have created a lattice pattern in some sort of polymer. Then they compare its behaviour to steel tubes. At least here in Denmark, most tall poles are already lattice structures, usually of steel. I wonder if this miracle material would perform well in a traditionally shaped lattice or if their new miraculous lattice would work even better with conventional steel?
In Murphy We Turst
It leaves out important facts, such as...
...strength is not the only important material property. The images only show this strength in compression.
Is this material resiliant? Strong in tension or compression? Does it shear easily?
ALL of these properties matter if you are going to use it. Usually, the Aeromet steels, super carbon composites and other superstrong materials suffer from poor non-strength properties, rendering them useless in most situations.
Imagine your super material 2 lb bike frame that chips away because it is so brittle that rocks chip off peices, or is too rigid because the material has no elastic modulos.
These MS Paint jobs remind me of "all your base are belong to pyramatrix" or something...
Also, watch out bringing up goats around here...
...and this lie crawls out of its mouth: 'I, the state, am the people.'
It's a new building structure, not a new building material. It may not even be a truely new structure at that, at least similar designs have been used for qite some time.
Lars T.
To the guy who modded me down from perfect to terrible Karma - Apple haters still suck
Now we can build 10,000 unit subdivisions in the desert at half the cost! Won't it be grand when we're all out of water?! I CAN'T WAIT!
(Yeah, this is a bit paranoid BTW, but I live in new mexico so give me a break. EL VADO LAKE is a mud hole and I didn't catch any fish this weekend so I'm bitter.)
Linux is dead.
LU
Yes, our patent office is doing it's job. They have granted a patent on the triangle! This is great news. I'm going to go out and patent the square! There's money to be made... Muahahaha! All Your Square R Belong To Me!
If you scale something in only one or two dimensions, then yes, the results will be horrible. Of course a person 6 times taller (but all other dimensions normal) will be in bad shape. However, if you scale it in all dimensions, they will do just fine--until they try to walk down main street and take a 6kV power line in the crotch.
Ditto on spider silk. Increase the length 100 times and yes, it's useless. Increase the length AND the girth 100 times, and you have something that could give fullerines a run for their money.
>However, if you scale it in all dimensions, they will do just fine--until they try to walk down
>main street and take a 6kV power line in the crotch.
Wrong. Expanding dimensions doesn't work because the physical size isn't the only consideration. Area expands as the square of the size, volume as the cube.
Increase the length and girth 100 times and the weight would increase 100^3 or 1,000,000 times. Your leg bones would snap like toothpicks.
Two examples of "movie myths":
Giant insects would be crushed under the weight of their own exeskeletons.
People the size of insects would have to eat several times their own body weight in food just to keep their body temperature constant.
ObTopicRef: A previous poster was right, strength in compression is only useful in specific applications. Take aerogel, for example. It can support 100 times its own weight in compression. Handle it the wrong way and it crumbles to itty bitty pieces.
Interesting enough, however I don't see this being a widespread replacement for steel unless it can be easily cut, rolled, bolted, welded and whatnot. I used to work for a company that developed structural steel detailing and fabrication software and can say from experience that making a connection between two pieces of steel is not exactly a trivial task. This structure just doesn't look like it would easily lend itself to building anything of significance other than poles.
There are many materials lighter and
stronger than steel. If that were the
only important criteria, all modern
structures would be made of carbon
fiber. Since structures are big, and
require lots of material, the most
important question is: how much does
it cost?
They are *not* claiming to have a new material, their "product" is simply a triangulated braced beam made of carbon or glass fibre. Woohoo, a well designed braced beam made of carbon fibre is lighter than a solid block of steel, well that's a major advance for engineering. NOT. The only slightly unusual feature is that the bracing extends beyond the longitudinal members, but if that significantly improved strength/weight ratio, everyone would be doing it already. In fact, some quick back-of-the-envelope work suggests that its a fair bit worse.
Structures made of carbon/glass composites are way to expensive to make to be any use in buildings (production is very labour-intensive), and I see nothing on their website to suggest they have successfully addressed this.
My guess is their business plan depends on either getting bought by someone clueless, or abusing the patent system to get royalties from general engineering companies. On that subject, I would really like to know what exactly they think is worthy of a patent? The angle of the bracing?
A question about this goat spider silk - does spider silk scale linearly? [...] What I wonder is if spider webs are similar - amazing properties on a spider scale, but pretty pathetic at a larger scale.
All materials obey the square/cube law (strength scales as the square of the scale, weight as the cube). The important number for cables is tensile strength per unit area. This number is independent of scale.
Spider silk and many other more common polymers have a tensile strength comparable to or greater than that of steel, while weighing much less. The down-side is usually that they stretch more when force is applied (lower elastic modulus).
-WolfWithoutAClause
"Gravity is only a theory, not a fact!"I rock climb. I use carabiners, specifically blackdiamond Locking D's with asymetrical gates. These are rated at 22 KiloNewtons. Some quick calculations: A newton = .2248 pounds. So: .2248* 1000(kilo)*22 newtons = 4946 pounds. Which is two tonnes approx. Ergo, 2 of my climbing 'biners can support two tonnes. Each carabiner weighs less than one half of a pound.
www.convert-me.com was my resource.
Am I not getting something here? It all seems wrong to me.
Sig (appended to the end of comments you post, 120 chars)
Okay, to summarize:
Actually you have the body temp thing wrong. As the size of the body increases, the percentage of surface area per body mass goes down. There was an article somewhere that talked about this w.r.t. to dinosaurs. The smaller you are the faster you lose body heat.
That's because they're engineers, not artists.
Yeah, and it's not as good a conductor as copper. What's your point? Spider silk can't be made into rigid structures, right?
Less than 10% can mean anything from 0% to 10%. It's shorter and more precise to state that it's 9% the weight of steel
Since it's a structure and not a pure material, it's not precisely amenable to such analysis. As they say in the company website, the weight ratio of a pure steel tube to a PYRAmatrix strut depends on the size and shape of the strut in question. Apparently the structure is more efficient and thus has a better weight savings over steel at larger diameters.
So you could say something like "it's 9% the weight of a steel strut 200mm in diameter with a load limit of 2000kg", but you couldn't give a single figure for all cases.
Furthermore, they apparently make this stuff out of more than one different material; I saw both glass and carbon fiber product listed on the site. It's safe to assume that different materials will result in different properties relative to steel in the final product.
So specifying a range like "less than 10%" is probably a perfectly valid generalization, as long as it's true for the majority of applications.
I stole this sig from someone cleverer than me.
yes, but this patent is for a geometry, not a material.
So you could use goat spider silk in your composite structure, using their geometry.
This'll make it easier for the neighborhood kids to climb to the top and electrocute themselves. I smell a lawsuit.
---If you can't trust a nerd, who can you trust?