Properties of TJ-1 Lunar Soil Simulant

Tongji-1 lunar soil simulant (TJ-1 for short) was recently invented by Tongji University, China. It could be used to construct testing ground in the preparatory impact tests of lunar landers under the extremely adverse condition in the Earth environment, where the interaction pressure between lunar lander and lunar soil has the important effect on the safety of lunar lander. The TJ-1 is originated from red volcanic ash deposits collected from northern China. The raw materials are firstly dried, crushed, and sieved to obtain materials of seven particle sizes. Gradation is then used as the controlling parameter to generate TJ-1 with desired mechanical properties. The TJ-1 demonstrates certain similarity to lunar regolith in physical and mechanical properties, and it is an ideal substitute of lunar regolith located from 0 to 30 cm below lunar surface in the mare region on the Moon. Compared with other simulants introduced in the literature, TJ-1 has an internal frictional angle as high as 45° at e=1.0 and hence is advantageous over other simulants when high shear strength is desired. The TJ-1 will be a good choice as a ground material in the preparatory impact tests of lunar landers in the Chinese Lunar Exploration Program.