Influence of gravity on the micromechanical properties of portland cement and lunar regolith simulant composites

Abstract

Concrete materials utilizing in-situ planetary resources are a promising option for construction on the Moon and Mars but the influence of variables, such as reduced gravity, needs to be understood. In this paper, we investigate the influence of gravity on the micromechanical properties of portland cement pastes that contain the lunar regolith simulant JSC-1A. Samples were prepared by astronauts onboard the International Space Station (ISS) and hydrated in microgravity (μg), lunar gravity (0.17 g), Martian gravity (0.38 g), and a statistical point at 0.7 g. Results were compared to a control sample hydrated on Earth (1.0 g). Specimens were analyzed by statistical nanoindentation and results for the paste suggest that gravity does not influence the in-situ mechanical properties of the hydrated phases. Results for the simulant give insight into the potential performance of lunar regolith as a component in a composite material. These results are critical to the continued development of lunar concrete technology.