模拟月壤的力学性能与本构模型研究进展

Significance In lunar exploration projects,understanding the interactions between lunar probes and lunar soil is essential. This necessitates a thorough investigation into the mechanical properties and constitutive relations of lunar soil. To gain a clearer understanding of these properties and the interactions between soil particles,this paper reviews and summarizes the research progress in the mechanical properties of lunar soil simulants through experimental studies and discrete element method(DEM) simulations. It aims to provide a reference for a deeper understanding of the mechanical and constitutive characteristics of lunar soil,as well as to analyze numerous mechanical problems encountered in lunar exploration. Progress Due to the high-vacuum and low-gravity environment on the moon,lunar soil differs greatly from earth's soil and exhibits unique physical and mechanical properties. However,given the scarcity of real lunar soil samples,lunar soil simulants with similar properties are utilized as substitutes. This paper focuses on the experimental and DEM simulation studies of various lunar soil simulants with different physical properties,examining factors such as tensile strength,shear strength,bearing capacity,soil-tool and wheel-soil interactions,and landing impact response. Furthermore,it evaluates the mechanical constitutive models for lunar soil simulants established based on these experiments and DEM simulations. Currently,there is limited research on the dynamic deformation characteristics of lunar soil simulants under vacuum and low-stress conditions,as well as on the damage caused by the failure of glassy cement in the soil. Therefore,conducting systematic and in-depth research on the dynamic deformation and damage evolution of lunar soil simulants is crucial. Understanding their dynamic deformation and damage evolution under vacuum and low-stress conditions and establishing a dynamic damage constitutive model for lunar soil under such environments are significant for accurately describing its mechanical properties. Conclusions and Prospects The paper points out the main issues in current research on the mechanical properties of lunar soil through experiments,DEM simulations,and constitutive models. 1)Experimental studies mainly focus on the static properties of lunar soil simulants,lacking research on dynamic properties under low-gravity and vacuum environments. This is insufficient for the dynamic data required for large-scale lunar sampling and lunar base construction. 2)DEM simulations of the dynamic performance of lunar soil simulants are rare,and the models often lack the unique structure of glassy cement in real lunar soil and the particle cohesion it causes,making it difficult to accurately reflect the dynamic deformation characteristics of the glassy cement under low-gravity and vacuum environments. 3)Most constitutive models are based on existing experimental data of lunar soil simulants under conventional static stress,with almost no dynamic damage constitutive models that consider the deformation mechanisms of lunar soil under low dynamic stress and vacuum environments. Thus,it fails to accurately describe the dynamic performance of lunar soil. Therefore,future research should focus more on the dynamic performance of lunar soil simulants. In addition,for constitutive models,efforts should be made to develop microscopic damage constitutive models based on the deformation and damage mechanisms of lunar soil simulants,as well as dynamic constitutive models that integrate machine learning with physical information such as deformation and damage. This will enable a systematic analysis of the dynamic performance of lunar soil simulants and lay a theoretical foundation for addressing related mechanical problems in lunar exploration projects.