Sunset in Mars (Photo via Shutterstock)
Could locally sourced building materials realize our Martian dreams?Retno Wulandari 28 April 2017 14:30
Have you ever thought of settling down in another planet? Mars maybe? Well, maybe you won’t be able to do that anytime soon, but at least, scientists have found an easy way to build a settlement using available materials from the red planet.
Mars’ red soil can be turned into bricks without any use of an oven or additional ingredients. Explorers who want to stay in Mars just need to press the soil to form a compact shape, with pressure equivalent of a blow from a hammer.
The finding has been proven through A NASA-funded study, authored by a team of engineers from the University of California San Diego, that was published in the Scientific Reports on April 27, 2017.
Though we might not need to relocate soon, but the research is important, as US President Donald Trump passed a bill in march directing NASA to dispatch a manned mission to Mars in 2033.
“People who will go to Mars will be incredibly brave. They will be pioneers. And I would be honored to be their brick maker,” said lead author and professor of structural engineering at UC San Diego Yu Qiao.
However, the idea of using Martian soil to build settlements for Mars’ manned mission is nothing new. But this is the first finding that allows astronauts to stay on the red planet with minimal resources. Some previous ideas including the usage of the nuclear-powered brick oven, or complex chemicals to turn Mars’ organic compounds into polymers to bind the brick.
Initially, in this research, engineers were trying to minimize the number of polymers used to shape the Martian soil into solid blocks and accidentally found out that none was needed.
The process requires two steps to turn soil into bricks without additive and heating. First, they have to fill a flexible container with a simulant. In this case, scientists use a rubber tube. Second, they have to tamp it by giving a high pressure until the simulant achieves a compact state. The amount of the needed pressure for a small sample is equivalent to the pressure occurs when someone dropped a 4.5 kilograms hammer from a height of one meter.
From this process, pallets of small red soil, about one-inch-tall, are produced. The pallets can be cut into brick shapes.
Bricks can be formed from Martian soil without binding agents, thanks to the iron oxide, a compound which gives the soil its signature reddish color. The researchers have investigated simulant’s structure using various scanning tools and found a coat of iron particles wrapping bigger rocky basalt contained in the simulant. The iron particles are characterized by clean, flat angles which allow it to bind to one another when pressed.
Researchers also found that the bricks are stronger than a steel-reinforced concrete, even without rebar.
According to the researchers, their brick-making method might be compatible with additive manufacturing technology. To build structures on Mars, astronauts have to add a layer of soil, compact it, then add an additional layer, compact it and so on.
However, further researches are still ongoing. In the next plan, researchers will try to increase the bricks' quality to see if it could be more effective and stronger.