Concrete
Concrete is a well known material for building settlement facilities such as houses and infrastructure elements. It has excellent characteristics for protection against radiation and small meteorites. Possibly, concrete can be made in situ on Mars, using local resources. Concrete is a mixture of cement, sand and stone in various proportions.
Contents
Cement
Hydraulic cement
There seems to be plenty of water on Mars, but hydraulic cement also requires calcium, silicon oxide (sand) and aluminum oxide. It is unclear whether these substances can be found on Mars in a form that allows a simple processing.
Sorel Cement
Sorel cement is magnesium based cement, a non hydraulic cement made from a mixture of magnesium oxide and magnesium brine. It has poor water resistance.
Sulfur cement
There are ideas of making waterless concrete from sulfur and regolith[1].
The ultimate strength and tensile strength was found to be best at a mixing ratio of 50% sulfur and 50% JSC Mars-1A regolith simulant sieved to a maximum particle size of 1 mm. The concrete was found to have a compression strength of > 50 MPa, a flexural strength of 1.75 MPa, and a splitting tensile strength of 3.9 MPa.
Utilizing sulfur-regolith concrete is possible on Mars, but not the Moon. On the moon, the concrete mass would be gradually lost due to sublimation of sulfur in vacuum, and the large temperature swings between lunar day and night which compromise the structure. Sulfur-regolith concrete is stable under martian conditions and would not experience a loss in mass due to sublimation.
Mars is considered a sulfur-rich planet, but it in unclear where sulfur may be and if it is present in a form suitable for the production of sulfur concrete.
An important disadvantage of sulfur cement is that is is not fireproof.
Sand and stone
Sand and stone are common on Mars. Most types of volcanic rock are compatible with concrete.
Reinforcement
The stability of concrete structures can be increased significantly by glass fibers or reinforcing steel. Concrete is often reinforced with rebar, steel bars that give it strength in tension.
See also
External links
- ↑ https://arxiv.org/pdf/1512.05461.pdf "A Novel Material for In Situ Construction on Mars: Experiments and Numerical Simulations." Lin Wan et al. 2016
