Discrete Element Modelling of Triaxial Compression Test of QH-E Lunar Soil Simulant under Hydrostatic Compression

Abstract—In this paper, triaxial compression mechanical properties of QH-E lunar soil simulant under hydrostatic compression path is investigated by using discrete element method (DEM) simulations. The volumetric strain characteristics of QH-E lunar soil simulant under hydrostatic compression path are discussed. The results show that volumetric strain gradually increases with the increase of confining stress. At low confining stress levels, volumetric strain increases quickly, when the confining stress increased gradually to the conventional levels, volumetric strain increases slowly, the volumetric strain curve becomes more and more flat. At the same confining stress, the volumetric strain increases with the increase of the initial porosity, while decreases with the increase of the friction coefficient. Under low confining stress, the gaps of volumetric strain caused by the change of porosity is not large, but at the conventional stress levels, the gaps of volumetric strain caused by the change of porosity become more and more larger. Meanwhile, the reduction of volumetric strain caused by the increase of friction coefficient under low confining stress is smaller than under conventional confining stress.