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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!
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)
Epoxy coating the re-bar has not been proven effective. What the masons you had a beer with is typical of the trades, they don't understand the big picture because they are focused on their job. No engineers or architects screwed up (other than the very few public examples of failure). Buildings are designed for a certain life, typically that's 50-70 years and after that the building is expected to need capital investment in the infrastructure beyond routine maintenance to extend that life. Buildings could easily be designed to last longer but the longer the life the higher the cost and it's rare for an owner to care. Buildings could easily be designed to take fires, earthquakes, tornado's and hurricanes but the costs of such design make it illogical.
The masons you mentioned talked about paint, it's not paint it's epoxy and it's a highly unproven technology (unless you are talking to the epoxy association, then it's the end all be all of re-bar protection). There are some in the engineering sector that think Epoxy coating re-bar is going to be one of those big mistakes that comes back and haunts us endlessly in a few decades (epoxy coated steel has been in use since the late 80's). The thing is concrete by itself is highly alkaline, the steel itself is alkaline as well and this prevents corrosion (which needs acidic environments to thrive, remember it's an oxidation process). The problem with epoxy is it negates the alkalinity effect of the concrete. In a perfect world the epoxy would be clean and perfect after the concrete sets but in reality the epoxy is going to have abrasions and cuts from erection, pouring and finishing (not counting what a decade of thermal expansion does to it). These abrasions in the epoxy coat provide a path of corrosion and once it penetrates the abrasion and infects the steel it can move along the steel much quicker because of the epoxy coat protecting the corrosion from alkalinity of the concrete. IMO a much better solution is galvanizing, the zinc coating has an additional alkaline protection and is much more durable during construction than epoxy ever can be. Either that or use high ksi stainless steel.
Boston is not alone in problems with re-bar corrosion, the issue involves the use of salt, cities and states that use salt in the winter on the roads, the salt provides the corrosion path and negates the alkalinity resulting in corrosion way ahead of schedule. The salt on the road moves through the environment and affects lots of ancillary structures including nearby buildings and tunnels. Black-bar re-bar used in concrete where salt isn't applied, even underwater and in freeze/thaw cycles has been very durable. There is reinforced concrete out there that is still in perfect shape that was poured 50 years ago and it's harder than ever.
Also, all concrete sets underwater, concrete doesn't dry, it hardens, it is a chemical reaction that involves hydration and the formation of a crystalline structure using the water. Without water there isn't concrete or if you allow the concrete to "dry" before it sets will degrade the concrete severely. This is why they have to keep the concrete moist for several days after pouring. Premature drying has similar symptoms to over-finishing, the surface of the concrete spalls the top surface off after a time rusulting in the loss of about a 1/4 - 1 inch of concrete on the surface spalling off.
And finally, organic additives to concrete are NEVER a good thing. Organics deteriorate after time, this leaves voids in the concrete where the organics ended up and the decay can create acids and bases that can adversely affect the concrete. Organics are bad, period. Now, Roman use of organics, such as blood may have resulted in more air-entrainment. The little tiny air-bubbles formed after the organics decayed (or as a result of mixing them in) would have provided freeze-thaw protection. Concrete placed in the open weather typically needs ~5% air entrainment to eliminate the effect of water saturation and freeze/thaw cycles. The heavy use of