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Crushed wood is stronger than steel

nature.com

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Re: Crushed wood is stronger than steel

#131

Post by mywittyname »

djrogers wrote: post #122
baud147258 wrote: post #102

Earlier quoted context omitted.

If the wood is load-bearing, once it has reached a sufficient degradation level, it'll collapse just as well as any steel beam. And since steel is usually embedded in concrete, it'll be protected for some time, increasing the time before it reaches a critical temperature and collapse. Still I thank you for your answer, it explained what I did not understand in your comment.

I think your assumption that steel is usually embedded in concrete is incorrect. It can be, but it's also often not. Have you never seen steel beam construction with exposed beams? It's not at all uncommon...

It's pretty much the standard in steel construction for beams to be exposed. Fire safety is the reason elevator shafts and stair wells of steel buildings are constructed from cinder blocks.

Re: Crushed wood is stronger than steel

#132

Post by aidenn0 »

tCfD wrote: post #108
willvarfar wrote: post #19

People may also find Pykrete interesting https://en.wikipedia.org/wiki/Pykrete Its adding wood pulp to ice to make the ice much much tougher. It was invented by the epitome boffin Geoffrey Pyke, who proposed they build an aircraft carrier of it! https://en.wikipedia.org/wiki/Project_Habakkuk

> epitome boffin Speaking of which, he's first cousin to Magnus Pyke - the guy usually remembered in the US (if at all) as the Professor shouting "science!" in Thomas Dolby's "she blinded me with science;" both on the song and in the video. In the UK he was, like his cousin Geoffrey, much better known for being the quintessential boffin, though Magnus self consciously played up this stereotype in his long television…

what does "boffin" mean in this context, is it like the US nerd, or (more recently) geek?

Re: Crushed wood is stronger than steel

#133

Post by Serow225 »

euroclydon wrote: post #39
jacquesm wrote: post #6

The most expensive wooden floors have the end grain exposed facing upwards and this is then compressed down, much like the top of a good quality butchers block. Those floors are just about indestructible. The heavier such floors are used the stronger they get! The wood in the article is compressed crosswise to the grain (so they get thinner rather than shorter), using the original planks as the raw organic material t…

Do you mind sharing a picture of this done right? The end grain wood floor pics I found on Google look mostly hideous to me.

I work at Red Wing Shoe Company, and our office has this type of flooring on the first floor: https://i.imgur.com/arWH5NR.jpg

Re: Crushed wood is stronger than steel

#134

Post by aidenn0 »

brudgers wrote: post #86
jacquesm wrote: post #6

The most expensive wooden floors have the end grain exposed facing upwards and this is then compressed down, much like the top of a good quality butchers block. Those floors are just about indestructible. The heavier such floors are used the stronger they get! The wood in the article is compressed crosswise to the grain (so they get thinner rather than shorter), using the original planks as the raw organic material t…

none of those ever made it to very high levels of industrial adoption. Non-exotic methods of strengthening wood, made it to high levels of production in spades: plywood, oriented strand board, microlam and glulam beams, and medium density fiber board (MDF) are direct examples. Wood I-joists and plate connected wood trusses are less direct. From a functional standpoint, standardization of lumber grades is a social tec…

Plywood is the best combination of strength, weathering resistance, and workability of any material I've yet used. MDF is way cheaper, but it is so much weaker pound-for-pound[1].

1: One carpenter I talked to complained that MDF won't hold screws, and apparently this is a common complaint, but if you drill properly sized pilot holes and use sheetmetal screws it's pull-out strength is fine, particularly since you need thicker MDF than ply, so you can use a longer screw.

Re: Crushed wood is stronger than steel

#135

Post by pbhjpbhj »

freehunter wrote: post #130
pbhjpbhj wrote: post #67

Earlier quoted context omitted.

I agree completely. The only part I disagree with its the claim wood is "barely biodegradable". Almost anything can be preserved.

If we're disregarding proper maintenance, almost anything can be biodegradable too. Steel will easily rust into dust in an alarmingly short period of time, but we have 100-story buildings made of un-rusted steel lasting for a century and maybe centuries more. Compared to cars from 5 years ago rusted into oblivion even while they're still being driven.

Rusting isn't biodegrading, it's chemical. Of course the lines aren't distinct, but they seem much clearer than you're suggesting.

Re: Crushed wood is stronger than steel

#136

Post by brudgers »

aidenn0 wrote: post #134
brudgers wrote: post #86

Earlier quoted context omitted.

none of those ever made it to very high levels of industrial adoption. Non-exotic methods of strengthening wood, made it to high levels of production in spades: plywood, oriented strand board, microlam and glulam beams, and medium density fiber board (MDF) are direct examples. Wood I-joists and plate connected wood trusses are less direct. From a functional standpoint, standardization of lumber grades is a social tec…

Plywood is the best combination of strength, weathering resistance, and workability of any material I've yet used. MDF is way cheaper, but it is so much weaker pound-for-pound[1]. 1: One carpenter I talked to complained that MDF won't hold screws, and apparently this is a common complaint, but if you drill properly sized pilot holes and use sheetmetal screws it's pull-out strength is fine, particularly since you need…

The primary advantage of MDF is dimensional stability. Dimensional stability is highly desirable for surfaces receiving veneers or high pressure ("plastic") laminate finishes. It's not really intended for structural applications, but for furniture and cabinetry it can be a reasonable option.

Re: Crushed wood is stronger than steel

#137

Post by ZenoArrow »

monochromatic wrote: post #110
brudgers wrote: post #86

Earlier quoted context omitted.

none of those ever made it to very high levels of industrial adoption. Non-exotic methods of strengthening wood, made it to high levels of production in spades: plywood, oriented strand board, microlam and glulam beams, and medium density fiber board (MDF) are direct examples. Wood I-joists and plate connected wood trusses are less direct. From a functional standpoint, standardization of lumber grades is a social tec…

There’s also stabilized wood. You basically fill all the space inside the wood with a hard resin. Small pieces are used for things like jewelry, knife scales, etc.

Your comment reminded me of a technique that guitar makers have been using in recent years, which is to make wood more stable by roasting it in a kiln (which removes the moisture from the wood, and supposedly increases its stability).

Re: Crushed wood is stronger than steel

#138

Post by thatcat »

jacquesm wrote: post #127
thatcat wrote: post #126

Earlier quoted context omitted.

After a bit of searching, the only descriptions of cutting board compression techniques I've been able to find are compressed perpendicular to your description. Do you have a good source for more info on axially compressed end grain flooring or cutting board construction techniques?

https://www.google.nl/search?q=butchers+block&client=firefox... Plenty of floor links already in this thread.

There are no links or threads related to axial compression. I guess your original post ment that it is compressed during use rather than constrution.

Re: Crushed wood is stronger than steel

#139

Post by logfromblammo »

dogprez wrote: post #99

Reminds me of Raymond Feist's Riftwar Cycle. The Tsurani's planet was devoid of metal so they had all wooden armor and weapons... uncomfortable silence

The Feist collaboration with Janny Wurts went into much more detail, and is in my opinion more readable than Feist's solo work.

Basically, as materials science goes, they skipped everything about metallurgy and went straight to ceramics, polymers, and composites. Seems like Feist took the concept from Teng-dynasty paper armor and just ran with it, including the pseudo-Asian flavor of the Tsurani.

Re: Crushed wood is stronger than steel

#140

Post by monochromatic »

usrusr wrote: post #113
monochromatic wrote: post #110

Earlier quoted context omitted.

There’s also stabilized wood. You basically fill all the space inside the wood with a hard resin. Small pieces are used for things like jewelry, knife scales, etc.

At what point do we have to stop considering processed wood as wood, but as a wood/resin or wood/adhesive composite?

Stabilized wood definitely has a lot more in common with resin than with wood, in its mechanical properties.
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