The video linked to by Gates' blog says "The most important material in terms of sheer mass in our civilization is cement made into concrete" "The chinese poured into their buildings and roads [...] as much concrete in just 3 years as United States in 1 century".
"In modern times, researchers have experimented with the addition of other materials to create concrete with improved properties, such as higher strength, electrical conductivity, or resistance to damages through spillage."
There's more available to concrete these days than what the US infrastructure used up to 2000. Not that 3 years consumption > 100 years consumption isn't impressive, but:
1) not only are we not comparing the same period
2) it's not clear we're comparing the same material
I often hear cement and concrete used interchangeably, but had the difference drilled into me when I worked (doing computer work) in the industry briefly. For that reason (cement != concrete) and potential advancements in concrete (maybe there are new composites that let us use a fraction of what used to be necessary?) it's not entirely clear what the numbers mean, outside of "China is growing fast".
The shrinking alone will cause some interesting effects.
There are a lot of lay-man misconceptions about concrete, one of the more persistent ones is that concrete needs to 'dry'. It doesn't, it needs to cure, it's a chemical reaction that gives concrete its strength, not something going into solution to allow pouring that then dries and solidifies.
Concrete is very interesting material, its history is fascinating and the materials science behind it as well.
Such a simple thing in principle, so incredibly complex. Just like glass another one of those materials with vast depth.
It's one of those deceptively 'unsexy' materials too from an outsider's perspective: think of steel and someone may think of, what, swords? watches? but think of concrete and someone thinks of brutalist architecture and urban decay. But there's no reason why concrete is any less fascinating and complex than steel.
What I suppose I'm saying is that it has a PR problem, and I'm glad people like yourself are leaving comments like that to help solve it :)
Now timber is different because it has some inherent structure built in. Much less frustrating and still quite flexible.
The consequences of getting concrete wrong can range from expensive to devastating.
but AFAIR, the conclusion was "we actually always knew, it's just that it takes too long".
> In case you need a refresher, cement is a powdery lime-and-clay substance that is combined with water and gravel or sand to make concrete.
An estimated 25-30% of China’s cement capacity is low-grade cement
not used in other countries (P.C. 32.5 grade).
According to the China Cement Association, low-grade cement products
(all 32.5 grade) accounted for 72% of the total cement output in China
in 2013, with the P.C. 32.5 grade cement accounting for 54%.
For comparison, South Korea's extraordinary growth was followed by a series of infrastructure failures in the mid-90s. A relatively new bridge suddenly fell into a river during the morning rush. A department store imploded, killing over 500 people. Gas explosions all over the place. IIRC none of the major accidents in Korea were caused by low-grade concrete specifically, but there seems to be a general parallel between what the Chinese have been doing lately and the "build now, worry about quality later" mentality that Koreans adopted during their period of rapid growth. Both result in crumbling buildings 20-30 years later.
If that's true, the expectation is already there. However, my impression is that this belief stems from this idea that construction will always be happening because that's how the economy rolls.
The question is what percentage of the population believes that this cycle really is the end game and what percentage of the population thinks they're investing into infrastructure what will last their entire life.
If what happened in Korea is any indication, the first generation of apartment buildings will be demolished after 20-30 years, homeowners will be "asked to leave" with as little compensation as the construction company can get away with, and a new block of condos will go up that the previous homeowners just can't afford. In Korea, at least we let the previous homeowners file complaints and protest for a while before we send in the bulldozers. In China, the bulldozers will probably go in first, and the GFW won't let anyone else know what happened next.
It took the wealth of a civilization to produce the Pantheon. We could make more durable buildings if we used stone, too, but do you really want to pay $10m for a house?
For example, anyone could write a dramatic headline declaring that we've created more computer chips in the last X months than in the 20th century. That doesn't mean much.
In short, this feel like some sort of crappy statistic handpicked to make China look bad, when in fact it's the whole world that's using a lot more concrete, not just China!
Why is progress in countries outside the western civilizations a bad thing?
Don't we want the people who make our iphones and oculus rift headsets and shiny usb-c devices to have apartment buildings to live in?
I'd rather they had nice houses instead.
It's very possible to have nice houses without endless suburban sprawl. They can indeed learn from our mistakes; have nice houses, but without endless suburban sprawl.
Secondly how are you going to build nice affordable houses for 1.4 billion people without sprawl. Are you suggesting completely giving up on urbanization and going back to having countless tiny villages?
Absolutely, but they either suffer from rapidly rising houses prices or no appreciable population growth. If you stick to a population ceiling of say 50k or so then many problems are easy
But we are talking about about places that are seeing up to a million new people show up in just a few years. Building everybody a nice house is neither realistic nor, in my opinion, desirable. We've either got to re-think the whole "everybody gets a nice house" or try to reverse urbanization in favour of lots and lots of small town capped at around 50k population.
So: the US did not "do the same in the last 5 years", and with China currently using cement at ~20 times the rate US is, the claim is very believable.
> And where many houses in the U.S. are made of wood, China suffers from a relative lack of lumber. Unlike in the U.S., many people in China live in high- or low-rise buildings made out of cement.
A critical argument, but unfortunately mentioned towards the end of the article. But overall its a interesting article and this gif  comparing Shanghai '87 vs '13, from it gives a good perspective of the modernization (akin to images of Dubai).
Dams, roads, bridges, factories, shipyards and large malls high-rise buildings is where the cement goes, and China is using ~20 times more than the US... My reading is that they are developing fast and catching up to the Western world in material standards of living.
The interesting question is...: how long will this momentum last, and will they keep going lont enough to overtake the current first world economies? I can see good arguments for both sides of this question.
History spanning back >5000 years, using either rocks, clay bricks (which require fire) or wood. North America has huge amounts of timber which wasn't exploited much until very recently, and a relatively low population for the size of the territory (even counting just the US, there were more chinese in 1900 than there are USians today, and the 1900 US population was below the Chinese population around year 1000… the two countries have almost identical surface areas).
Europe doesn't build with wood either, ignoring wood not being a very good construction material for high-density urban spaces, there's nowhere near the amount of raw materials you'd need lying around, and not enough room to grow it in the quantities necessary.
Oh and much of the Chinese territory is completely unfit for lumber growth (too arid, too montainous, or both), and what little would be fit is necessary for food production. China already imports ridiculous amounts of timber as it is.
It's also hard to fireproof without modern technology. But you can still build in modules and with modern technology the cost difference isn't that great for low rise areas. Not far from here there's an 8 story building completely built with wood, and higher buildings are not unheard of. For detached family sized houses it's the standard choice. I wouldn't be surprised if it's the same throughout Canada, northern US and parts of Russia.
Wooden construction for buildings over a certain size has been outlawed in Norwegian cities and all of Norway historically, so it's actually mostly concrete and stone, although small towns have mostly wooden, detached homes.
> Revisit: Walton, 2008
> Kevin revisits David and Greta Iredale, who replaced their original house which they designed and built themselves with a German built, precision engineered Huf Haus.
> Esher, 2004
> Kevin McCloud follows a couple who have built houses before, but never on this scale. Their new 'Huf Haus' is designed and made in Germany but delivered for assembly in Surrey.
Not log cabins, but wood framed "Fachwerk" houses are everywhere in Germany, or at least Bavaria.
I'm perfectly fine with brick-and-mortar houses (and concrete sky-scrapers). Brick houses have less fuel for fires, better load-bearing properties (pros), although they take longer to construct.
Brick is just siding. What's the frame made out of?
You can use wood, you can use steel, you can use concrete with rebar. Those are your only real options.
In the US, you will frequently see 2-3 story houses framed with wood and with a brick siding. I'm in one right now. Anything higher than 3 stories will be done with steel or concrete.
Wood is cheaper than steel and lasts for hundreds of years if properly cared for, which is why it's preferred for smaller residential structures.
Man, that is going to be a shock to my house that has all of the outside walls, and parts of the foundation, made from brick. Just because your house has a brick veneer doesn't mean that's the only way to do it.
In my particular the case the floors and roof are made from wood. The floor joists rest on the brick walls.
For brick an mortar houses, the "frame" is also made of brick. All the walls are load-bearing, so there is no actual frame + siding: just brickwork. You have a concrete foundation, then you lay your double-thick brick-walls (for all load-bearing sections - all of the outer walls that are expected to support roofing trusses). Internal walls can be a single-brick wide. The only place timber is used is for roofing.
Brick. It's bricks all the way down...
To be serious: most houses in India are made of bricks.
There are quite a few all stone building from the dark ages made entirely from stone. Nothing but stone. Not even mortar, I think. They look very similar to modern buildings. If you moved into one today, it wouldn't be a lot less comfortable than it was then.
Byzantine & later Turkish architecture used brick domes and arches as roofing in buildings that are still in good condition. If you stand on the roof, it feels more like a hill than a building.
Same way as usual, except you use concrete or metal for beams, and e.g. http://en.wikipedia.org/wiki/Hollow-core_slab between the beams. For brick, archways e.g. catalan vaults, you can do pretty amazing things with brick archs: http://www.lowtechmagazine.com/2008/11/tiles-vaults.html
> Even if it's a single story, how do you make a roof?
You can do them the same way, though a wood bent to support e.g. a tile roof tends to be more common (having just a wood bent is a far cry from a wood house).
Unreinforced masonry, by contrast, is a terrible choice for an earthquake zone. It's heavy, brittle, and has approximately zero tensile strength.
After digging some more, it seems like cost is another factor.
I suspect our backgrounds subconsciously color our opinions though: my childhood home (and 99% of homes I have ever visited) were brick and mortar, maybe that is why I am partial to it.
A rammed earth building becomes a pre-dug grave when there's an earthquake.
It's a strange US tradition. It's also regional. Until 2002, New York State prohibited most wood construction, and Chicago still restricts it severely. On the other hand, in earthquake country, unreinforced brick is prohibited.
(I live in a cinder-block house. It was built in 1950 by a commercial builder as his own residence, and he built the structure like a commercial building. It's very solidly built. This is quite unusual for Silicon Valley.)
Bricks are a problem in earthquake prone regions. Even brick cladding on wooden frames tends to fall off and hit people on the head.
A little historical perspective would help as well. Check how many houses are made of wood in New York City. A reminder: a large number of cities in China have a longer history than New York City.
In Beijing, there are some thujas (cypress-like trees) around but I agree that Beijing winter is not very colourful. And the yellow wind (i.e. sandstorm from Gobi) that you're about to get there just now isn't nice either, despite being a natural phenomenon.
We haven't had real bad dust storms since 2008, though a few days last year were bad. And the wind does blow out the pollution so....
Singapore, a modern city by any other definition, uses concrete in the same way so they can import cheap construction labor from India.
Steel was strictly state-controlled. It had a status of "strategy" material. So it was "scarce". The first generation of uber-rich families were created because these families (of highest government officials) could get their hands on these strictly controlled materials. They simply sold the rights of these materials, not the materials themselves, to the manufacturers at a hefty price.
Steel is heavily used in manufacturing and there is a glut of it now. I hope the day of reckoning for the aristocrats is near.
The risk of a crisis is very real; even if the risk of default is low, the risk of the marketing seizing up because no one wants to buy at a price sellers are willing to sell at is incredibly real.
Rents in Beijing are pretty cheap now, getting cheaper actually, while housing prices remain rediculously high. Heck, my apartment complex is prime but only about 60% occupied (the other units bought but being held for speculation alone). Something has got to give.
Since year 2000, China's household debt has gone from 8% of GDP, to now 40% of GDP as a ratio (the US is 75% by comparison). Mortgage debt has become a common problem in China. At the rate household debt is expanding in China, they'll be up to 60% in four years or so.
A main reason people buy properties is the lack of other type of investment. The public in general have no confidence in stock market. Housing is the only thing almost guaranteed to make money. As financial reforms such as allowing investing overseas kicks in, we should see money moving away to housing market.
Home equity is about 55-56% in the US for the entire housing market (owner occupied) and has continued to climb since the lows of the post bubble bust.
That said they've obviously been investing at an outrageous rate since 2000 in modernizing themselves. The U.S. has started on that way before and without centralizing planning in the same way has done it more slowly over time (with a smaller population in 2015, let alone 1900. Important to realize the U.S. population has grown a lot over the past century).
Here's a nice intro from Joel Cohen, a longtime leader in the field:
After increasing dramatically during the first half of the 20th century the growth rate has declined for the last 40 years. Looking more deeply into the demographics (by country and age group) it is pretty clear that this decline will continue for many decades to come. The video I linked above goes into some of this.
Most experts currently predict that the world's population will peak (i.e. below zero population growth) middle of this century around 9 billion - although a few say as high as 11 billion or as low as 7 billion. These predictions are way down from just a decade ago.
Still its a demonstration of unbound budgets. The future cost of maintaining it all will be the test of time. While much has been made of China's ghost towns quite a few are getting people yet I am curious as to the maintenance being done and in a timely manner. There is also the question of quality, there have been a few newsworthy stories out of China of shoddy construction.
In fact, the bigger issue in the western world, and eventually the whole would will be dealing with it, is what happens when this slowdown in births happens. Just as when you got a huge economic boom from having many young people, you get a economic drag when all those people age and have less young people to support them.
If you subtract the 15% unoccupied rate from your link from the 6.6 gigatons of concrete, it's still a lot more than the U.S. used in 100 years.
It does make the news when San Francisco's residents start getting driven out of the city. It does make the news when Madison limits the height of buildings downtown. Can you give me an example of people who didn't get a flat tire today? Of course not, because that's just called normal functioning.
but this only happens in the US, right? not anywhere else, like... china?
Also, china doesn't have a property tax, so you can just buy an apartment and sit on it forever, there is no economic pressure (as a property tax is) to put it to productive use.
It is speculated that China will drop the land use grant when they institute a real property tax.
Edit: looks like things have gotten worse for Ordos: http://gizmodo.com/4-instant-cities-that-are-still-completel...
If you handed out hukous in 3rd tier economically depressed new cities, I'm not sure if there would be many takers. And the properties in Kangbashi are all fairly high end anyways, the city hukou-deprived migrant workers probably wouldn't even be welcomed.
China builds a lot of subsidized public housing on the city outskirts of major cities, but no one wants to live there because transportation is bad to where the jobs are.
Usage in the U.S. took a nosedive in 2008, I assume because of the recession. Pre-2008 shows a local maximum in 2005 of 128 megatonnes; so still an order of magnitude less.
(because, for instance, the bitumen in asphalt roads is also a cement)
-The concrete recipes I remember always had sand and rocks, gravel and/or pebbles (depending on local availability)
Lines of code have to be examined in detail to figure out their impact, concrete is the universal component of construction, if more concrete is used there will be more construction going on.
I don't want to dub any specific piece of software the Three Gorges Dam of code. But it surely is out there.
That and it's common usage would probably make it a great linkbait story...
For further reading check out an answer on Quora  where I found the McKinsey Global Institute report.
P.S. I imagine using cement is more eco-friendly.