Behavior of Geosynthetic Reinforced Soil Structures in Martian Simulant: A Pioneering Experimental and Analytical Study

Due to the unique properties of Martian soil and hostile environmental conditions, the development of stable foundations and other geotechnical structures on Mars is essential for future human habitation. This study evaluates the effectiveness of geogrid reinforcement in a custom-prepared Martian Bright Eroded Mantle (BEM) soil simulant with physical models adapted from geosynthetic reinforced soil (GRS) abutment model setups. Geogrid spacing and material stiffness were varied independently. Displacement behavior was measured by laser displacement sensors and the ultimate bearing capacity was compared against Federal Highway Administration (FHWA) predictions. The unreinforced model collapsed during filling, while reducing spacing to 100 mm increased capacity nearly eightfold relative to 200 mm. Higher reinforcement stiffness also improved capacity, from ~80 N with glass-fiber to ~180 N with acrylic geogrids, though gains diminished at the highest stiffness. Failure consistently occurred by wall–soil wedge sliding, with geogrids bending instead of rupturing, showing that flexural resistance, rather than tensile strength, governed performance. A new analytical model accounting for sliding and bending was created that better fits the model. This study pioneers a scalable methodology for small-scale testing of alien soil simulants, guiding future extraterrestrial geotechnical design.