Programmable Cement Makes Stronger, Cheaper Future Homes

Cement is the most basic material used in constructions today. There has been a lot of improvements with cement being fire-resistant, bendable and self-healing. Now, scientists have developed a programmable cement that would make for stronger and cheaper future homes.

Scientists at Rice University, under the leadership of Rouzbeh Shahsavari, have studied on how to make cement stronger and greener. By looking on the nano level, the scientists were able to study the crystallization of calcium-silicate-hydrate (C-S-H), a study published in Cement and Concrete Research said. They were also able to synthesize specific shapes of the C-S-H particles.

The team of scientists was able to form the cement particles in shapes of cubes, rectangular prisms, dendrites, core-shells and rhombohedra. These kinds of shapes are easy to pack together, making for a denser cement. The packed shapes will keep water out and other materials from worming through the cement, thus destroying the structure.

The programmable cement shows the advancement in technology where one can control the size and shape of the cement. The programmable cement is also self-assembling particles that quickly form into microstructures that are more densely packed, making them stronger.

In order to form the shape of the programmable cement, a mixture of calcium silicate and surfactant compound are exposed to carbon dioxide and ultrasound. If the mixture has a lot of calcium silicate, it will form clumps of spheres and interlocking cubes while less amount of calcium silicate in the mixture would make for more spherical shapes and smaller cubes.

The now shaped programmable cement adheres to the surfactant and self-assembles into the larger versions of its shapes. By adjusting the concentration of the particles, temperature and duration of the process, the team was able to control the amount, shape and size of the programmable cement. By mapping it into a morphology diagram, the programmable cement can be used to customize the creation of structures with specific construction properties.

In order to test the strength of the programmable cement, Shahsavari and his team used a nano-indenter to individually crush the particles of the programmable cement. According to the scientists, this is the first time cement is tested not in a group but through its individual particles.

The team hopes that with programmable cement, which is stronger, denser, durable and cheaper, better and cheaper homes can be built. The programmable cement is also much greener as it less porous, thus reduced emission of greenhouse gasses. The study was published in the journal, Journal of Materials Chemistry A.