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Sticky Rice Is the Key To Super Strong Mortar
lilbridge writes "For over 1,500 years the Chinese have been using sticky rice as an ingredient in mortar, which has resulted in super strong buildings, many of which are still standing after hundreds of years. Scientists have been studying the sticky rice and lime mortar to unlock the secrets of its strength, and have just determined the secret ingredient that makes the mortar more stable and stronger. The scientists have also concluded that this mixture is the most appropriate for restoration of ancient and historic buildings, which means it is probably also appropriate for new construction as well."
Based on experiences with my dishwasher, I can also predict that buildings made with oatmeal or cheese will also stand the test of time.
Many of which are still standing, 2000 years later.
I predict the common factor may be the concrete.
hth.
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I didn't know the critical ingredient was a mystery. Alton Brown from Good Eats explained the molecule quite well in the rice episode, and my immediate thought was "oh that must be why it was used in mortar for the Great Wall and such."
Ancient Chinese Secret
sounds like a job for the MythBusters!
So is this a good time to invest in California calrose growers?
"Common sense will be the death of us all"
Yes, we do have enough rice.
We have enough food production that no one should go hungry.
People go hungry due to politics and poor distribution, not overall quantity of food.
Don't know something? Look it up. Still don't know? Then ask.
you'll shit bricks.
You're wrong, I'm afraid. Although the rice used in Sushi is sticky, it's not what is generally called sticky/glutinous rice. Sticky rice is used in various Asian, especially Thai dishes, either with savoury food like pork, or as a dessert with fruit such as with mango or durian, and salty coconut milk.
Jack Daniels and broken dreams?
...provide this information to BP?
Dear BP,
Scientists have concluded that sticky rice/lime mortar is the most appropriate for restoration of ancient and historic buildings.
How is that oil spill thing going?
Best regards,
some guy on ./
0 = 1 + e^(Alt something)
Mortar that's too strong is brittle, meaning it can easily crack. Rebar can rust and swell, breaking this brittle cement. The result is catastrophic. I learned this from a couple of masons who I was drinking with at a pub. They joke that because of some really bad decisions made by architects and structural engineers in the 1960s and 1970s, they have good job security. I had known from reading books on restoring historical masonry buildings (thanks Ian Cramb) that strong mortar such as portland cement and other more modern mixes are just too brittle to be used as mortar. Stones and bricks shift ever so slightly as they settle. This can cause cracks, large or small, in the brittle mortar, that wouldn't happen with a weak lime mortar. These cracks are the widened by water freezing and thawing, and sometimes plant life. But what my bar buddies told me is that what makes the problem even worse is the rebar used in concrete buildings until recently would slowly rust and swell, so the masonry would burst from the inside because it was so brittle. These mason fellows would chip out the remaining concrete or cement, clean and coat the rebar (but sometimes replacing it) with a protecting paint, and then re-apply cement or concrete. I've noticed this problem occuring in many places, such as subway stations and bridges in the Boston area. I have no reason to believe the problem is limited to this city.
Regarding Roman cements and concrete: pozzolana, otherwise known as hydraulic cement, was a mixture containing volcanic ash, specifically from mount Vensuvius. It has the ability to dry and set underwater. This 'secret' is said by many to have been lost for many centuries, but in fact was kept a 'masonic secret' by some masonic guilds for a long time. Yet the exact nature of this secret and its revelation are hazy.
Yes, blood was used as an ad-mixture to some Roman cements. I can't remember what benefit it added.
Some places add organic material to concrete, with a variety of results. Done correctly, it increases the strength of concrete. Done badly, it's a recepie for disaster. Using straw is certainly bad, but evidently hemp and possibly other materials can be used. Exactly what works under given conditions is not known to me. It may be another one of the 'masonic' secrets.