PHYSICAL AND MECHANICAL PROPERTIES OF LUNAR REGOLITH

The lunar surface is almost completely covered by a dark gray layer of debris, lunar regolith, with thicknesses in the range of 2 meters to 20 meters. It is created by meteorite and micrometeorite impacts, high diurnal (day/night) temperature difference, solar wind and cosmic ray bombardment.The surface layer consists of crushed bedrock, fine-grained rock and mineral fragments, meteorite residuals, polymict regolith breccias, and fused glass. Thus the loose regolith layer is ready-to-excavate mineral product, which is not necessary to drill and blast. The special formation process of lunar regolith leads to different properties from soils on the earth. This paper listed the average and best estimated value of physical and mechanical parameters at Luna and Apollo landing sites. These parameters are particle size distribution, particle shape, specific gravity, porosity and void ratio, electric conductivity and electromagnetic parameters, coefficient of compressibility, bearing capacity and shear strength. These parameters are significant for the design and operation of engineering equipment, lunar base siting and construction, and resource utilization.