Want better concrete? Dilute the cement

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On April 2, 2019

Photo of adding CO2 to Lime Water solution to create CO2- ions and HCO3- ions. And then testing with a Ph meter probe

Dr Hongyan Ma and grad research assistant, Lizzie Popoola, EMgt’20, perform research on creating Calcium Cabonite Nanoparticles in concrete.

It’s long been proven that adding nanoparticles to concrete improves strength and durability, but the cost of such processes has outweighed the benefits. Missouri S&T’s Hongyan Ma is working on a safer, simpler and potentially more affordable method of combining nanoparticles with concrete.

Ma, an assistant professor of civil, architectural and environmental engineering, compares the technique to blowing bubbles into limewater.

“Our method is to create calcium carbonate nanoparticles inside the concrete by blowing carbon dioxide into the highly diluted wet cement,” says Ma. “The nanoparticles will be formed inside this part of the suspension in the presence of siliceous ingredients, and you use that to mix the concrete.”

Previous attempts to add nanoparticles into fresh concrete were not successful because the superfine particles would always stick together — not disperse, says Ma. His method involves forming the nanoparticles inside the fresh concrete, creating an even disbursement.

A $160,000 grant from the National Science Foundation will allow Ma to test his method through 2021. By then, Ma hopes to have the technology available to make it ready for existing concrete plants to use.

Ma’s method would address another potential problem of working with nanoparticles in concrete — the fact that they are harmful to humans. Their harmful side effects include potential lung inflammation and heart problems, especially when dry nanoparticles are used.

“Our method is a wet method, so the workers and the laborers at concrete plants will not be exposed to the harmful nanoparticles,” Ma says.

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On April 2, 2019. Posted in 2019, Around the Puck, News, Research, Spring 2019