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Tokyo To Build 350m Tower Made of Wood (theguardian.com)
A skyscraper set to be built in Tokyo will become the world's tallest to be made of wood. From a report: The Japanese wood products company Sumitomo Forestry Co is proposing to build a 350 metre (1,148ft), 70-floor tower to commemorate its 350th anniversary in 2041. Japan's government has long advertised the advantages of wooden buildings, and in 2010 passed a law requiring it be used for all public buildings of three stories or fewer. Sumitomo Forestry said the new building, known as the W350 Project, was an example of "urban development that is kind for humans," with more high-rise architecture made of wood and covered with greenery "making over cities as forests." The new building will be predominantly wooden, with just 10% steel. Its internal framework of columns, beams and braces -- made of a hybrid of the two materials -- will take account of Japan's high rate of seismic activity. The Tokyo-based architecture firm Nikken Sekkei contributed to the design.
the same as a duck?
This automatically translated article talks about fire safety in high wooden houses: https://translate.google.com/t... Unfortunately the images didn't come along, but they can be seen in the original article: http://www.husbyggaren.se/bran...
Where I am, building code prohibits wood for buildings over 4 stories (though they're talking about allowing it for up to 5 or even 6 because the builders don't want to pay for concrete, and their lobbying is amazingly effective) Combined with the requirement for all buildings over 4 stories to have elevators, we have a ton of 4 story apartment buildings. We've also proven repeatedly that wood is a HORRIBLE material for any multi-family building, as we've had quite a few burn to the ground leaving hundreds of people homeless. Of course each time they say that if only they'd made this minor tweak to the building code the disaster wouldn't have happened, but then the next one happens despite whatever tweak they say will solve it.
When I read this, I immediately wondered why it was even possible to build a 1,100 ft tall wooden building, more than eight times taller than the current record for the tallest wooden building. This Guardian article goes into more detail about the engineering of tall wooden buildings, and cites this Canadian Wood Council case study for some of its information. In short, the wood materials to be used are highly specialized fireproofed laminate composites. Calling the finished product wood is like calling Splenda sugar; just because it's a derivative of the original doesn't mean it's the same thing.
From an engineering perspective, a skyscraper undergoes incredible stresses. The building has to be capable of supporting itself and all the weight within it. It has to withstand the tremors of earthquakes, the forces of wind and water, and not lose its strength over time, even as it's exposed for decades to UV rays. The building materials need to have a unique combination of sheer strength, tensile strength, and compressive strength. A combination of steel and concrete give you all three. But natural wood is inconsistent. Flaws like knots and cracks in the grains weaken its sheer strength. Wood has great tensile strength in the direction of the grain, but is very weak against the grain. And it works the opposite way with compression. The only way to overcome these weaknesses is with laminates, which are very expensive (currently, due to the lack of demand) to produce.
Not to mention wood burns much easier.
My personal opinion is that there are some architects trying to get name recognition by coming up with something unique. I hope anyone considering to fund such imaginations take a lesson from the Spruce Goose and use wood when it's advantageous, not avant garde.
This has already been done.
Well, consider the 67.3m Grenfell Tower which burned spectacularly last June, killing seventy people. The tower was reinforced concrete, but it was the decorative polyethylene cladding that transmitted the fire at deadly speed, and the interior apartment furnishings that actually killed people.
So it's quite possible for a concrete building to become a fire trap; it's the superficial bits that are the risk. Massive wooden structural members might burn in theory, but like an over-large log they wouldn't catch fire quickly.
So I should think that a large wooden building could in principle be engineered to be for all practical purposes as fire safe as concrete building. The problem is knowing that something is safe in practice. Engineering is as much about the application of experience as it is induction from general principles. So if you build far beyond the limits of experience, you can never be quite certain of the behavior of a system.
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
The whole skyscraper will be made from engineered lumber. Not for rot necessarily, but for consistent dimensions, stability, strength, etc.
W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
First of all, that story is from 2017. It isn't news.
Second, from the story, "The latest problems were discovered with shipments of more than 11,000 tons of steel, copper, and aluminum products made by Kobe Steel and its affiliates in Japan, China, Malaysia and Thailand."
So the actual true claim closest to the lie you told would be, "Being owned by a Japanese company doesn't magically cause product inspections to happen."
They're one of the world's biggest steel company, so 11k tons isn't actually very much.
No reports of problems at this point, only of faked test data. So some steel plants in "Japan, China, Malaysia, or Thailand" didn't do the testing for some of the products. This doesn't mean that there was a quality problem, only that there was a quality control problem. The people running the factory probably saw a long history of passing the quality tests, and decided to save some money and not do them. That's bad, especially if the parent company doesn't detect it and correct the problem.
But the story seems to really be that because Japan is so good at quality control, they discovered the faked test data even before it resulted in undetected problems in actual product quality.
It is already well known in the world that if you product comes from "Japan, China, Malaysia, or Thailand" that there might be variations in quality. Duh. I think people understand that whenever a product came from "Country A, Country B, Country C, or Country D." Duh. Does that mean that Country A had a bad reputation? No. No it does not.
Aluminum and vinyl siding are things because they're cheaper than wood.
If they were better, they'd either be more expensive, or wood siding would have been discontinued.
Also, consider this: in a tall building, the siding is not the structural support. So the subject isn't even about the siding. This building could have vinyl siding and the story would be the same story about a wooden building.
Also, you don't have to paint the wood for protection. There is also technology that places the protective chemicals inside the wood, instead of heaping it on top. Then you don't reapply protection, ever.
Carpenter bees are not a legit threat to wooden structures. Compare: Carpenter ant.
Popular advice says that you shouldn't compost such wood chips. Small amounts go in the trash.
Disposal is a good question, for which good answers are available. In "throw away" cultures, the question has implicit assumptions of "doing it cheaply" or engaging in landfill habits.
In Japan and elsewhere, advanced incineration seems the preferred solution.
http://www.bvsde.paho.org/bvsa...
Apparently counterintuitively wooden beams handle fire better than steel beams. In a normal fire of 750-1000 degrees celcius the steel will lose 90% structural integrity while wood only 25% after 30min. This means the steel beam will have collapsed long before its wooden counterpart has.
http://www.nzwood.co.nz/faqs/w...