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One of the objectives of the fourth phase of China's lunar exploration program is to detect water in the permanently shadowing region of the moon's South Pole.It is highly likely that there is water ice in the form of ice and dust in the permanent shadow area at the bottom of the pit.Therefore,ground simulation and mechanical properties of aquiferous lunar soil are the prerequisite and guarantee basis for the exploration of water ice materials in lunar soil.In this paper,the physical and mechanical properties of the polar water-bearing lunar soil were studied and the section samples for drilling and sampling were prepared.Based on the characteristics of lunar soil samples obtained by Apollo series lunar probes,the mineral composition and morphology of lunar soil in the polar region were analyzed,as well as the grain size distribution,porosity ratio,porosity and relative density of lunar soil profile along the depth direction.To analyze the source of the permanently Shadowed areas water ice,from the preparation of cementation process can realize degree,economy and particles of different preparation plan is than the feasibility,determine to "water soil mixed+hierarchical compaction+gradient refrigeration" sampling task to carry out the prophase preparation plan as drilling profile on soil sample preparation methods.The uniaxial compressive strength of water bearing lunar soil was tested by wDW-100 cryogenic electronic universal testing machine under ultra-low temperature.Based on the obtained stress-strain curve data,the relationship between compressive strength and water content of the water-bearing lunar soil was studied to analyze the factors influencing the compressive failure of the water-bearing lunar soil,and to reveal the mechanism of water content affecting the cementation strength of the lunar soil particles.The elastic modulus of lunar soil samples with different moisture content was calculated and the influence of moisture content on the elastic modulus of lunar soil was analyzed.Based on computer software,the cooling process of profile samples with different configurations was simulated,and the variation rule of temperature field inside the sample was obtained.By comparing the cooling time of samples,it was found that the cooling rate of hollow profile samples was significantly faster than that of solid profile samples,and the simulation results were used to guide the configuration design of profile samples.Based on The Janssen continuum model,the equilibrium relationship between the thin section elements at a certain depth in the static compaction process was established to provide a reference range for the compaction height of lunar soil layers in the profile.The low temperature bath cooling and low temperature compacting device of section water-bearing lunar soil samples were designed,and the statics simulation analysis of the low temperature compacting device was conducted.Based on the low-temperature compaction device and the preparation process of profile samples,the polar section lunar soil samples with equivalent soil mechanical parameters and coverage in the mechanical rigor of lunar soil drilling and sampling were prepared for ground validation.A mechanical load model of the penetration of steel needle into lunar soil was established based on the Moore-Coulomb strength theory and limit equilibrium conditions,and the disturbance mechanism of the penetration of steel needle on lunar soil was analyzed.In ultralow temperature under the condition of different moisture content of the equivalent static penetration test simulation in soil profile,obtain the moisture content of different sample unit penetration resistance values,by unit of penetration resistance and uniaxial compressive strength of the contrast analysis,penetration resistance fitting unit--the uniaxial compressive strength curve,strong mechanical strength test curve equation,get the profile sample It provides a stable and reliable method for testing the strength of drilling sample section.