Do they manufacture Super-Wood ?
December 13, 2012 3:35 PM Subscribe
Do they make lumber interlaced with steel wires, which is much stronger than regular lumber?
I saw a documentary about the manufacture of multilayered plywood ---- they actually peel a tree like an apple, interleave the tree peels in different orientations, and glue them back together to make a board which is much stronger than a regular board.
This, and the reinforced-concrete concept ((rebar makes a concrete wall much much stronger)) got me wondering if anyone manufactures 2x4s , 2x6s , etcetera, which have steel wires deliberately laced through them, to make them much much stronger than regular pieces of lumber.
What is the state-of-the-art in enhanced lumber products?
I saw a documentary about the manufacture of multilayered plywood ---- they actually peel a tree like an apple, interleave the tree peels in different orientations, and glue them back together to make a board which is much stronger than a regular board.
This, and the reinforced-concrete concept ((rebar makes a concrete wall much much stronger)) got me wondering if anyone manufactures 2x4s , 2x6s , etcetera, which have steel wires deliberately laced through them, to make them much much stronger than regular pieces of lumber.
What is the state-of-the-art in enhanced lumber products?
I've never heard of anything like that. It sounds incredibly labor intensive and complicated. When you have other options, like glulams or steel beams, I'm just not sure it would be cost-effective.
posted by amanda at 3:47 PM on December 13, 2012
posted by amanda at 3:47 PM on December 13, 2012
One big appeal of the standard 8' 2x4 is that it costs about $2.50, and, based on the history of structural failures of wooden homes (or lack thereof), is already pretty much "strong enough".
posted by tylerkaraszewski at 4:03 PM on December 13, 2012
posted by tylerkaraszewski at 4:03 PM on December 13, 2012
You couldn't cut the reinforced lumber with any standard woodworking tools. That would be a huge disadvantage. I searched for "steel reinforced lumber" and saw a few articles about attaching steel plates on the outside of joints and members.
posted by scose at 4:07 PM on December 13, 2012
posted by scose at 4:07 PM on December 13, 2012
The boat building folks have played with all sorts of wood to other materials laminations. Cold-molding (ie: laying up veneers with resin over a form) with carbon fiber, kevlar or fiberglass layers isn't unheard of.
And beyond the basic gluelam beam concept, the construction industry has played with layers of wood over various insulating materials, like foam, or using fiberboard layers in plywood for smoother surfaces.
posted by straw at 4:14 PM on December 13, 2012
And beyond the basic gluelam beam concept, the construction industry has played with layers of wood over various insulating materials, like foam, or using fiberboard layers in plywood for smoother surfaces.
posted by straw at 4:14 PM on December 13, 2012
Part of the strength of plywood is that the glued layers are "cooked" and adhere firmly to one another. Compression finishes this adhesion and complements it, but it's mostly the glue that keeps the plywood together.
I can't think of any kind of glue that would adhere to both wood and steel in a way that would create a material of consistent strength. Uniformity of characteristics in wood products is a huge thing.
That is if you wanted to put a whole layer of steel within the plywood.
If you wanted to place steel wires in between the layers, I can see how the strength of the plywood would be actually compromised, as in the compression and heating process, the steel would very likely break the fibers. In wood, strength of material depends almost entirely on the quality of the fibers. That is why they capitalize on the fiber strength by placing it in perpendicular directions.
I am not sure that I am using the right terms in English, but wood mechanics was a big part of my university studies (forestry).
posted by Tarumba at 4:28 PM on December 13, 2012 [3 favorites]
I can't think of any kind of glue that would adhere to both wood and steel in a way that would create a material of consistent strength. Uniformity of characteristics in wood products is a huge thing.
That is if you wanted to put a whole layer of steel within the plywood.
If you wanted to place steel wires in between the layers, I can see how the strength of the plywood would be actually compromised, as in the compression and heating process, the steel would very likely break the fibers. In wood, strength of material depends almost entirely on the quality of the fibers. That is why they capitalize on the fiber strength by placing it in perpendicular directions.
I am not sure that I am using the right terms in English, but wood mechanics was a big part of my university studies (forestry).
posted by Tarumba at 4:28 PM on December 13, 2012 [3 favorites]
It seems to me that it wouldn't be all that strong. Wire re-enforcement works in concrete because concrete resists compression incredibly well and the wire helps hold it together or, if the wires are stretched before the concrete is set, then it's got an extra dimension of strength from the pre-tensioning.
Compared to concrete, wood is like jello. If you put wires in jello, it wouldn't be much stronger than just the wires alone.
posted by bonobothegreat at 4:31 PM on December 13, 2012
Compared to concrete, wood is like jello. If you put wires in jello, it wouldn't be much stronger than just the wires alone.
posted by bonobothegreat at 4:31 PM on December 13, 2012
I have also never heard of wood reinforced with steel wires.
I did see a mention one time of a glulam beam where the bottom layer (where the greatest tensile load occurs) was a graphite fiber composite instead of wood.
posted by Bruce H. at 6:24 PM on December 13, 2012
I did see a mention one time of a glulam beam where the bottom layer (where the greatest tensile load occurs) was a graphite fiber composite instead of wood.
posted by Bruce H. at 6:24 PM on December 13, 2012
Parallam.
It's strong, and beautiful enough to use for furniture.
posted by weapons-grade pandemonium at 6:27 PM on December 13, 2012
It's strong, and beautiful enough to use for furniture.
posted by weapons-grade pandemonium at 6:27 PM on December 13, 2012
There is a lot of great engineered wood out there, but not that involve steel wires that I have ever seen. Laminated with metal sure, but usually that is for looks or just a surface finish, not strength.
posted by MrBobaFett at 6:40 PM on December 13, 2012
posted by MrBobaFett at 6:40 PM on December 13, 2012
As others have said, the strengths of steel and concrete complement each other, while wood is a good small-scale material in both tension and compression. Also, in a nearly divine coincidence, steel and concrete have close to the same thermal expansion coefficient, so they react to temperature changes roughly the same and they don't tear each other apart - reinforced wood would likely fully delaminate after a year or so, depending on the climate. Also, reinforced concrete is constructed in a way that would be difficult to replicate with reinforced wood: there's either precast pieces that you generally don't want to cut, or you build a cage out of rebar and then pour concrete around/in/through the cage. The rebar has indentations and knurls to help adhere it to the cured concrete, which aren't quite easy to create with wood. One of the big advantages of regular lumber construction is that it's totally plastic - you can change your mind and cut something differently and not compromise the strength of the material. If you add steel to it, you may lose some of that ability.
Engineered wood products these days are common, especially since larger harvestable trees are more rare, which makes it harder to get larger beam sizes without going to engineered lumber of some sort. So, there's glu-lams, paralams, microlams, and wood I-joists, which are kind of a hybrid.
There is a technique to reinforce wood with steel, called a "flitch plate", but that's really a wood/metal/wood sandwich that's bolted together.
Another thing is that once you get to the kind of spans or loads where a steel-reinforced wood piece would be useful, you may have a building large enough that you're not allowed to build it out of combustible materials anyway.
posted by LionIndex at 7:25 PM on December 13, 2012 [1 favorite]
Engineered wood products these days are common, especially since larger harvestable trees are more rare, which makes it harder to get larger beam sizes without going to engineered lumber of some sort. So, there's glu-lams, paralams, microlams, and wood I-joists, which are kind of a hybrid.
There is a technique to reinforce wood with steel, called a "flitch plate", but that's really a wood/metal/wood sandwich that's bolted together.
Another thing is that once you get to the kind of spans or loads where a steel-reinforced wood piece would be useful, you may have a building large enough that you're not allowed to build it out of combustible materials anyway.
posted by LionIndex at 7:25 PM on December 13, 2012 [1 favorite]
There is significant use of resin to strengthen the properties of wood ... as mentioned above this is quite common in low cost boat building. In many respects this would be correctly termed "super wood" ... but it does not use metal.
Here are a few reasons why you don't see it.
Wood and metal expand and contract at different rates ... sticking (more correctly bonding) a piece of wood to a piece of metal is actually quite hard to do well, for just this reason. Hence structural bonding of wood sheet and metal sheet is out.
Interweaving wire mesh into a bonded wood product, such as ply, whilst possible, would not really increase the strength of the final product, would require infill of resin, and ... when it begins to rust, the entire piece is compromised as the cancer travels the length of the mesh delaminating as it goes.
posted by jannw at 5:12 AM on December 14, 2012 [1 favorite]
Here are a few reasons why you don't see it.
Wood and metal expand and contract at different rates ... sticking (more correctly bonding) a piece of wood to a piece of metal is actually quite hard to do well, for just this reason. Hence structural bonding of wood sheet and metal sheet is out.
Interweaving wire mesh into a bonded wood product, such as ply, whilst possible, would not really increase the strength of the final product, would require infill of resin, and ... when it begins to rust, the entire piece is compromised as the cancer travels the length of the mesh delaminating as it goes.
posted by jannw at 5:12 AM on December 14, 2012 [1 favorite]
A couple of links pertaining to state-of-the art in enhanced lumber:
Pressure Cooked Wood
Timber Welding
Not wood, but Fibre Reinforced Concrete
If you're really interested, periodicals like Detail have a section about the latest building-related materials technology in each issue.
posted by Kiwi at 6:48 AM on December 14, 2012
Pressure Cooked Wood
Timber Welding
Not wood, but Fibre Reinforced Concrete
If you're really interested, periodicals like Detail have a section about the latest building-related materials technology in each issue.
posted by Kiwi at 6:48 AM on December 14, 2012
This thread is closed to new comments.
posted by StickyCarpet at 3:39 PM on December 13, 2012 [2 favorites]