Sulfur-based materials for martian construction: Pioneering sustainable extraterrestrial building solutions

The overarching purpose of this study is to devise sustainable construction materials and techniques for Martian infrastructure, with the primary research problems centered around the numerous challenges posed by the Martian environment, such as water scarcity, extreme temperatures, etc., in order to construct resilient structures using local resources. The study's design encompasses a series of experiments where Martian bricks are fabricated with varying components (including Martian soil (MS) simulant and different aggregates), bond thicknesses, and recycling iterations. Compressive tests on cube specimens and four-point bending tests for bond strength are carried out, with a parametric study focusing on variables like MS simulant percentage, aggregate types, and bond thickness. Key findings reveal that MS simulant enhances brick compressive strength (20 % content gives 25.2 MPa on average), 3 mm is the optimal bond thickness (balancing 1.42 MPa bond strength and workability), Fe₂O₃ aggregates have the highest compressive strength (39.2 MPa) and SiO₂ aggregate provides stronger bonds, and sulfur-based bricks are recyclable with slight strength reduction. The novelty lies in using sulfur as a bonding agent, pyramid-shaped structures for load distribution, empirical equations for prediction, and the recyclability of bricks. This offers a comprehensive solution for sustainable Martian construction. • Develops recyclable bricks and bond for Martian construction, enhancing robustness without water. • Demonstrates a compressive strength of 33.4 MPa with 20 % SiO 2 aggregates and a 80 % ES binder. • Utilizes molten sulfur as bonding agent, achieving durable connections between Martian bricks. • Develops numerical models for predicting the compressive behaviors of Martian bricks. • Proposes pyramidal structures, leveraging ease construction and geometric stability.