Mechanical Properties and Durability Performance of "Waterless Concrete"

Since water is not a universal commodity on the moon as it is on Earth, sulfur concrete, which does not require water to make, can be used as an alternative building material. Sulfur concrete consists of molten elementary sulfur and aggregates. The aggregates in lunar environment will be lunar soil and rocks. Sulfur is present on the moon in Troilite soil (FeS) and by oxidation soil iron and sulfur can be produced. Sulfur concrete specimens were cycled in two conditions: between room temperature and –27, and room temperature and liquid nitrogen (∼–191°C) to simulate exposure to a lunar environment. Cycled and control specimens were subsequently tested in compression. Test results showed that due to severe temperature cycling (between room temperature and ∼–191°C), compressive strength of cycled specimens was 20% of those non-cycled. Similar sulfur concrete mixtures were strengthened with short and long glass fibers. The glass fiber was derived from lunar regolith simulant. Glass fibers were pulled from the melted lunar regolith simulant and were used to reinforce sulfur concrete. Prisms beams strengthened with glass fibers were tested in 4-point bending test. Beams strengthened with glass fibers exhibited an increase in the flexural strength by as much as 40%.