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MIT Discovery Means Next-Gen Concrete Could Last for 16,000 Years

Civil engineers at MIT are currently exploring ways to create concrete with reduced creep that will be able to last for 16,000 years. Concrete is one of the most frequently used and widely produced man-made building materials on earth, with over 20 billion tons produced per year globally. The use of new ultra high density concrete will have enormous environmental implications, given its ability to deliver lighter, stronger structures capable of lasting many civilizations, while drastically decreasing the carbon emissions sent into the atmosphere by its inferior predecessor.

sustainable design, green design, building material, concrete, franz-josef ulm, mit, high density concrete

One of the researchers behind the new discovery, Franz-Josef Ulm offers, “More durable concrete means that less building material and less frequent renovations will be required.” Ulm, alongside Matthieu Vandamme, has identified the cause of creep (the time-dependent deformation of structural concrete). This discovery may lead to the development of longer lasting concrete, by increasing its density and slowing its creep by a rate of 2.6.

“The thinner the structure, the more sensitive it is to creep, so up until now, we have been unable to build large-scale lightweight, durable concrete structures,” said Ulm. “With this new understanding of concrete, we could produce filigree: light, elegant, strong structures that will require far less material.”

With regard to environmental impact, the annual worldwide production of concrete creates between 5 and 10% of all atmospheric CO2. Ulm explains, “If concrete were to be produced with the same amount of initial material to be seven times normal strength, we could reduce the environmental impact by 1/7. Maybe we can use nanoengineering to create such a green high-performance concrete.”

Ultra high density concrete could deliver exponential results both in terms of strength and durability, and is undoubtedly poised to redefine architects’ relationship with man’s most reliable building material while literally changing the face of the earth.

+ MIT

Lead photo by Jeff Kubina

5 Responses to “MIT Discovery Means Next-Gen Concrete Could Last for 16,000 Years”

mikeyjikey Says:

June 17th, 2009 at 5:50 pm

I think this is a bad idea – we should not be building things that last for 16,000 years. What a bitch that will be to take down once we decide that we don’t want to live in manmade caves anymore.

BuilderSYD Says:

June 17th, 2009 at 9:14 pm

Ok so it’s stronger and lasts longer (16000 years would be useless for many reasons, unless it’s containing nuclear waste at the bottom of an ocean) that’s all good but I think the claims on material and environmental savings are exaggerated.

The majority of concrete is used in the production of floor slabs, walls and columns in building structures. The depth of a slab depends on several things but they are about as thin as they can get, in many structures acoustic performance limits the ‘thinness’ of slabs and some walls especially in composite construction. Thus stronger concrete is not required. There is also the issue with thinner beams, walls etc in bending, more steel will be required to resist the actions due to reduced lever arms of the thinner profiles thus saving on one material will increase the use of another material with just as high an environmental impact if not higher. Thus a reduction of environmental impact of 1/7 just seams impracticable. You can get better impact saving by using materials such as PFA or GGBFS which are bi products of existing processes and can reduce cement use by 40%.

The article does not say how the ultra high strength or higher density is achieved, I would expect it is with the addition of admixtures which can be hazardous to the environment and expensive. For gravity structures the increased density would be beneficial but will it be cost effective? And how much denser is it? If you would save a few cubic meters for every hundred poured for a large mark in price up in price it just won’t be worth it.

When talking about ‘green/sustainable’ solutions you really need to keep your feet on the ground and be careful of perceived headline benefits without looking at the whole life cycle.

Although I am sure it makes for interesting research and would be helpful in some situations for the vast majority of uses it just would not be practicable.

Abe Froman Says:

June 18th, 2009 at 10:06 am

Uh, you are both idiots in your own special way.

AJ_AggregateIndustries Says:

June 19th, 2009 at 4:08 am

Nice to see some constructive debate being created, (no pun intended). The concept sounds interesting and the points BuilderSYD makes about the depth of slabs being limited by other factors, such as acoustic performance are completely valid. However, I imagine the methods being used to create it would have to be based on the current ones for ultra high-strength concrete using a combination of microsilica, high-range superplasticisers and carefully temperature-controlled curing regimes.

Microsilica is a by-product of the production of silicon and ferrosilicon alloys for the IT industry and, as such, does not constitute a big detrimental effect on the environment. Also, the current generation of superplasticisers, based on polycarboxylate ethers (PCEs), and used to reduce the water content of the concrete are not energy intensive to produce. Therefore, I would suggest that it is possible to create this high-strength mix without using unduly environmentally harmful components.

On a side note, 16,000 years is not all that impressive – some of the earliest examples of its use have already been standing for over 5,000 years and there are many examples of Roman use of the material from later on, such as the Colosseum.

Derek Says:

June 25th, 2009 at 6:25 pm

When will it be commercially available? The sooner we can bring it to market, the sooner we can create more American Jobs and opportunity and be suppliers to the world for this advanced concrete and manufactuing process.

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