Strength Properties of JSC-1A Lunar Regolith Simulant

Abstract

The paper presents a description of physical properties and a characterization of shear strength behavior of JSC-1A lunar regolith simulant. Specific gravity of solids, particle size analysis, and minimum and maximum index densities were measured according to ASTM standards. A series of axisymmetric triaxial experiments were conducted on JSC-1A specimens at two densities and a wide range of confining pressures. The stress-strain and volume change behavior of JSC-1A is presented and discussed. The results show that the peak friction and dilatancy angles are highly influenced by specimen density and confining pressure. Two models were developed to predict the peak friction and dilatancy angle, as a function of relative density and mean effective stress at the critical state. It was found that JSC-1A closely resembles the morphology and specific gravity of solids of some of Apollo regolith samples reported in the literature. Shear strength properties are presented within the framework of Mohr–Coulomb and friction-dilatancy theories. The effect of reduced moon gravity on strength parameters is also presented and discussed.