The amazing timber - Bamboo

[onetrack]

I was reading the chest-thumping argument about timber for props on WreckFline, and I had a thought - no-one has yet mentioned Bamboo, when it comes to a structural material.

This is the stuff they build scaffolding out of, across all of Asia - let alone the amount of housing made out of Bamboo. I can recall various articles spouting the massive advantages of Bamboo - its "green" footprint, its massive regenerative ability, it has no need to be fertilised or cared for, it just grows (really fast), and it's dirt cheap. I also discovered that Bamboo puts 30% more oxygen back into the atmosphere than any commercial timber tree.

 

But then, doing a little more Internet research, I find that some clever researchers in Zurich are investigating Bamboo composites as the world's new, clean and green, construction material. The name they are using is BambooTech.

These researchers have devised a Bamboo product that utilises Bamboo fibres mixed with an organic resin (about 10% resin), which product is then compressed to produce a material which is stronger than carbon fibre, stronger than steel, and only 25% of the weight of steel. The initial idea is to replace steel as a reinforcement in reinforced concrete with this product.

 

They say the product can also be used in multiple other manufacturing and construction fields, replacing PVC piping, being used for parts in vehicle manufacturing, and even be used as a structural component in buildings.

Some researchers in the U.S are already looking at utilising Bamboo in Cross-Laminated Beams, for multi-level construction projects. I would really like to see Bamboo timbers and composites take off, as it has the potential to provide a good income for many people in underdeveloped parts of the world, such as numerous Asian and South American countries.

 

I have no idea if a Bamboo composite could replace the likes of Sitka Spruce in aircraft, in airframes and propellors, but the potential appears to be there to investigate the promising potential of a Bamboo composite for these uses.

 

https://interestingengineering.com/innovation/bamboo-as-a-replacement-to-steel

 

https://www.dezeen.com/2015/11/04/bamboo-fibre-stronger-than-steel-dirk-hebel-world-architecture-festival-2015/

 

Edited August 23, 2022 by onetrack

[rgmwa]

A decade ago a group of us spent five weeks travelling through China. Driving through an industrial suburb on the outskirts of one city, Li Jiang I think, we passed the local equivalent of Coates Hire and saw great bundles of bamboo of different diameters and lengths stacked up in the yard. Obviously the local scaffolding suppliers. It hadn’t occurred to me until then that there would be such a place, but of course it made perfect sense. 

[onetrack]

There are something like 1400 species of Bamboo throughout the world - but one from Colombia, named Iron Bamboo (Guadua angustifolia) or Colombian Thorny Bamboo (no guessing where it got that name from), is already in wide use throughout South America as a construction material.

 

On the Guadua angustifolia site below, check out the "crushed Bamboo beams" (under "Products" - then "Crushed Mats" - then scroll down), which are a fairly crude CLB, still containing a lot of air spaces, but which beams apparently have astonishing structural strength.

 

https://www.guaduabamboo.com/blog/guadua-angustifolia

 

If you go to the home page of Guadua Bamboo, you'll see they list 90 types of Bamboo used for Building and Construction. It's interesting to see that Bamboo grown on slopes has greater tensile strength than Bamboo grown on the flat valley floors, and Bamboo grown on poor rocky soils has more solid trunks than Bamboo grown on rich soils.

 

 

 

Edited August 23, 2022 by onetrack

[pmccarthy]

The Cessna T-50 was known as the Bamboo Bomber but unfortunately I don’t think it’s wooden construction included any bamboo.

[Bruce Tuncks]

Sounds like just the material for building planes. But for gliders, the main thing about carbon is its stiffness. The high-aspect ratio wings of big modern gliders would twist enough to bugger up the spanwise loading if the material was more flexible.

So the elastic modulus E really matters here.

 

[Old Koreelah]

11 hours ago, onetrack said:

…clever researchers in Zurich are investigating Bamboo composites as the world's new, clean and green, construction material. The name they are using is BambooTech.

These researchers have devised a Bamboo product that utilises Bamboo fibres mixed with an organic resin…

Decades ago, some satellites were built on a subrame utilizing bamboo fibres.

[red750]

I have a bamboo pillow. And then there's Step One bamboo undies. Get some!

[facthunter]

I don't think it's actually a timber. Cane is like some grasses and has nodes as do some vines.   Nev

[red750]

From Wikipedia:

 

Bamboos are a diverse group of evergreen perennial flowering plants making up the subfamily Bambusoideae of the grass family Poaceae. Giant bamboos are the largest members of the grass family.

 

 

[old man emu]

I think that this promotion of bamboo as a renewable replacement for metals is simply an attempt to panda to the environmentalists.

[onetrack]

Here's another interesting video on Bamboo - not so much as a high-tech step-up with composite Bamboo - but just one lass utilising Bamboo in its natural form for building, mostly in Bali.

 

Elora Hardy is a Canadian girl of partly French ancestry (born in 1980) who was raised in Bali up to the age of 14 by her Canadian parents who ran jewellery stores in Bali.

She left Bali at age 14 to live in America, where she acquired a Degree in Fine Arts. She spent a number of years in the U.S., and ended up in the fashion industry, and spent time in NY designing prints for Donna Karan.

 

In 2010 she returned to Bali and started up IBUKU, her design company that utilises local Bamboo and Bali artisans, designers and architects, to construct unique homes and other structures in natural Bamboo.

Her construction work is something like Grand Designs - but largely in Bamboo. Most of her constructions are in Bali, but she has also built Bamboo structures in the U.S. and in Polynesia and in Hong Kong.

The secret behind her building work is simply treating the Bamboo with a Borax treatment, which preserves and strengthens the Bamboo, and makes it insect proof (natural Bamboo is very prone to insect attack, and degradation by mould).

 

As a fine arts designer cum architect, with a clever brain for unique design and construction, she has produced some stunning building results using Bamboo. As she explains, it's all about working with the natural shape of Bamboo to produce the desired result - obviously working on the labour-saving techniques of the early wooden ship builders, who would select an appropriately-curved Oak limb to use for hull frames, thus saving time and effort, and a lot of wood, instead of carving a solid length of Oak to shape the frame.

 

https://ibuku.com/

 

 

 

 

[Yenn]

Bamboo is a wonderful material and I have several different stands of bamboo, but as someone pointed it it could be pushed just to satisfy the greenies.

When you come to use it you will find it is very good in compression, but it does not bend well. it is also really like a hollow pipe with multiple joints, plus it is quite slippery, so hard to tie securely. The actual usable material for anything such as furniture or flooring would have to be fairly short lengths of narrow woody material. The use of it in large beams or strips must involve cutting and glueing in some form. My favourite use for it is as bushwalking poles for which it is excellent being strong and resilient, but don't run your arm down it as the surface can inflict a friction burn very easily.

Lovely stuff but surrounded in B/S. One use I have seen is made up floor boards and they warp with differing humidities. A floor of cupped boards does not look good.

[facthunter]

Wasn't there a song called "The House of Singing Bamboo?"  Nev

[red750]

Bamboo has been used in kitchen cutting boards. And we have two bamboo spatulas.They don't scratch the non-stick cookwear, and may scorch but do not catch fire.

 

I remember seeing a meme of Greta Thunberg complaining about the Chinese cutting down all the trees to make chopsticks. Someone corrected her to say they were bamboo.

[onetrack]

The Chinese have constructed toy helicopters from Bamboo for over 1700 years. These toys fascinated the Europeans when they appeared there in the Middle Ages. Leonardo da Vinci developed his ideas of human flight after studying them.

 

https://en.wikipedia.org/wiki/Bamboo-copter

 

 

[willedoo]

I have a stand of bamboo growing on top of a dry rocky hill. It's one of those varieties that don't spread; it just stays in it's neat clump year after year. It's a type suited to a drier area and survives droughts with no problems. My place is termite city, but I've never seen them attack a piece of dry bamboo here. I don't know whether bamboo is generally termite resistant, but mine seems to be.

[onetrack]

There seems to be a variation of opinions on whether Bamboo is attacked by termites. Some say yes, others say no. I'd have to opine that it may depend on the variety of termite as to whether they decide to eat Bamboo.

The technical paper at bottom talks of termite attack on Bamboo.

The greatest enemy of Bamboo is insects such as the Bamboo Powder Beetle. Not found in Australia (but Quarantine is on permanent alert for it appearing, as it travels the world via shipping and via infected Bamboo).

 

Bamboo Powder Beetle is found all through Asia and many of the worlds Tropical regions. The other thing that affects Bamboo is mould, fungi and bacteria - the inner layers of Bamboo can become mouldy and crumble.

I'd hazard a guess this is only a major problem for Bamboo in wet or Tropical areas. 

 

The Borates from the Borax treatment apparently affect the gut of any insect that might fancy a chew on Bamboo. The borates apparently damage insects digestive system, by interfering with enzyme activity, and the insects effectively starve because they can't process the ingested timber cellulose. The actual precise biological mechanism as to how boron works to kill insects is still not fully understood.

 

The Borax treatment for Bamboo also seriously inhibits the development of mould, fungi and bacteria, so it's a win-win treatment.

 

https://www.ctahr.hawaii.edu/gracek/pdfs/240.pdf

 

Edited August 26, 2022 by onetrack

[old man emu]

On 26/08/2022 at 10:05 PM, onetrack said:

Borax treatment

Interesting, short paper. Using borax as a means to control insects, mould and fungi would please those of us who are fed up with having manmade chemicals pushed at us for that task.

[Bruce Tuncks]

I treated a pinus door-step with borax years ago and it is just fine. All I did was put borax into warm water with a cupful of borax powder and then brush it on roughly.

But it is not used in treated permapine. I wonder why not.

[old man emu]

1 hour ago, Bruce Tuncks said:

All I did was put borax into warm water with a cupful of borax powder

That's a good recommendation. I am going to be using some untreated pine for noggings, so I'll paint the cut ends with a borax solution to stop any termites having a chomp. I found a short length of pine in the ceiling that was hollowed out by the termites. All that was left was a paper-thin wall.

[onetrack]

The sleepers utilised on the initial laying of the Trans-Australian Railway during WW1 were all treated Karri sleepers, with the treatment designed to ensure they were termite-resistant and rot-proofed.

 

Karri was rarely used for sleepers or for positions where it's buried in the ground, due to the fact that termites love eating it, and the fact that Karri can also be prone to dry rot.

But Karri is a tough, very stringy wood, and for structural strength in long lengths, it can't be beaten.

 

The treatment given to the Karri sleepers was called "Powellising" - the timber was soaked in a hot solution of Molasses and Arsenic, and then allowed to cool slowly. The Powellising treatment method was quite successful if carried out properly, but the process was so controversial prior to the T-A Railway being laid, the Govt actually called a Royal Commission into the treatment process, and the proposal to utilise Karri sleepers for the T-A Railway.

 

The Powellising process produced mixed results earlier, due to numerous operators carrying it out, and some of these treatment operators didn't carry out the treatment process correctly, so the results were mixed.

Numerous experiments were carried out with the various timbers, and a number of the Eastern States timbers gave mixed results for durability.

But the Powellising treatment worked well on Karri, and in the end, Powellised Karri was used for the entire length of the T-A Railway, after initial proposals were to use Karri only on the Western end of the Railway.

 

The T-A Railway line was completed on 17th Oct 1917, and the vast majority of the Karri sleepers used in it lasted until the late 1930's, a lifespan of around 20 years, which was regarded as quite satisfactory for timber sleepers.

 

https://trove.nla.gov.au/newspaper/article/228831401

 

https://trove.nla.gov.au/newspaper/article/196793095

 

I also found that Sodium Fluoride was utilised in some of the earlier rot-proofing and termite-proofing processes, but it was only mentioned briefly, and I found no mention of it being used widely.

 

Edited September 4, 2022 by onetrack

[red750]

 

 

[facthunter]

I found out the "House of Singing Bamboo" was a film that came out just after the end of the war.  Nev

[old man emu]

On 05/09/2022 at 11:29 PM, red750 said:

 

 

Some interesting carpentry techniques exhibited here. But look at the nature of the material she's using.  Try getting material of a similar nature in Temperate climates where all the material is solid from core to bark. Simply tubing with a wall diameter of about 6 mm (1/4"), and it is soft. However if you look at the material itself as she is working it, you can see why it can be used for scaffolding and more permanent structures. 

[Old Koreelah]

Thanks Red for posting this classic; I’d forgotten about this Living World Treasure.