Concrete is the 2nd most used material on the planet after water and is widely involved in modern infrastructure. It is made out of coarse aggregate, water and cement. Cement acts as adhesive giving the final mixture significant strength that increases over time.
Scientists investigate how a concrete mixture would react in microgravity conditions to examine the potential of building in extraterrestrial environments such as Mars or the Moon.
“On missions to the moon and Mars, humans and equipment will need to be protected from extreme temperatures and radiation, and the only way to do that is by building infrastructures on these extraterrestrial environments. One idea is building with a concrete-like material in space. Concrete is very sturdy and provides better protection than many materials,” Aleksandra Radlinska, Assistant Professor of Civil and Environmental Engineering at of Pennsylvania State University, stated.
The project included testing different cement powders and additives and changing the powder-to-water ratio used in the mixture. They found that gravity affects the properties of the mixture. Concrete made in space is much more porous and probably less strong than conventional concrete. Apparently, the hardening process is quite different in space than in earth. "Increased porosity has direct bearing on the strength of the material, but we have yet to measure the strength of the space-formed material," Prof. Radlinska said. However, the findings should be considered encouraging as the mixture developed and hardened.
Researchers stated that the conditions of the experimental procedure may have affected the results. For example, cement was transported in sealed small bags and did not interact with the space environment. "The samples were in sealed pouches, so another question is whether they would have additional complexities in an open space environment," Prof. Radlinska added.
For more information about the experimental procedure conducted in space, watch the video below.