Engineers increase strength of cement by 40% with shrimp shells

Researchers from Washington State University and the Pacific Northwest

National Laboratory have created tiny crystals and fibers of chitin from seafood waste. Nanoparticles increase the strength of cement by almost 1.5 times. 

In his work published in the journal Cementand Concrete Composites, researchers studied the behavior of chitin nanoparticles. Unlike cellulose, which is also used to increase the strength of cement, this material has an additional set of atoms at the molecular level. Thanks to this, scientists can control the charge on the surface of the molecules and, therefore, their behavior in the cement mortar. 

The study showed that addingProcessed chitin nanocrystals in cement improves its properties, including its consistency, setting time, strength and durability. They saw a 40% increase in concrete's flexural strength and a 12% improvement in its compressibility. In addition, the modified composition hardened for an hour longer. This is necessary to increase the range of transportation and construction in hot climates.

Researchers study the strength of cement under pressure. Photo: Washington State University

The shells of crabs, shrimp and lobsters areabout 20–30% is from chitin, with most of the rest being calcium carbonate, another useful cement additive. At the same time, from 13 to 17.5 million kg of fish industry waste is produced annually in the world. Most of them are simply dumped into the sea.

Cement production is carbon intensivea process that requires the use of fossil fuels to achieve the required high temperatures (1,500 °C). The limestone used in its production also undergoes decomposition, which produces additional carbon dioxide. At the same time, classic concrete cracks easily, which reduces its durability.

The authors of the work believe that replacing limestone with chitin nanoparticles will help reduce energy costs, the volume of garbage from seafood, and also increase the durability and wear resistance of cement buildings.

Read more:

Scientists filmed a strange creature with tentacles, which they mistook for a flower

On the moon, they found a place where the temperature is always comfortable for humans

AI has appeared that monitors processes and proposes new laws of physics