Advanced Martian construction: High-strength ISRU bricks, robust sulfur bonding, modular assembly, and FEA-verified pyramid habitats

Sustainable habitat construction on Mars faces significant challenges, including low atmospheric pressure hindering hydration, reduced gravity complicating compaction, and large habitat pressure differentials. This study presents an integrated In-Situ Resource Utilization (ISRU) approach combining high-strength regolith bricks, hydration-free sulfur bonding, and a modular pyramid habitat design validated by Finite Element Analysis (FEA). Optimized mechanical compaction (40 MPa) of nano-SiO2-enhanced Martian regolith simulant effectively bypasses hydration constraints, achieving compressive strengths exceeding 20 MPa even at ambient temperatures. A systematic parameter study (pressure, particle size, water content, temperature) yielded predictive design equations and demonstrated potential strength enhancement up to 44.5 MPa with thermal treatment (1000°C). Furthermore, a robust, hydration-free sulfur-based mortar was developed for modular assembly; optimized flat-cut interfaces yielded bond strengths exceeding 2.0 MPa, crucially shifting the failure mode from the bond interface to the brick material itself (ensuring a reliable minimum tensile capacity >1.2 MPa). Leveraging these advancements, a pyramid-shaped habitat module, advantageous for Martian environmental loads (including a 101.3 kPa internal pressure differential and 3.71 m/s2 gravity), was designed. FEA, incorporating experimentally derived material properties (e.g., 22 MPa compressive strength, 1.2 MPa tensile/bond capacity), confirmed the structural integrity, with maximum predicted tensile stress (1.15 MPa) remaining below the bond limit. This research provides a comprehensive, experimentally validated framework—from material development and bonding to structural application—for constructing resource-efficient, durable habitats on Mars, significantly advancing solutions for sustainable extraterrestrial infrastructure.