Abstract

Significance In pursuit of a profound comprehension of the intricate mechanical characteristics exhibited by lunar regolith throughout lunar construction endeavors，and to meticulously scrutinize the efficacy of lunar surface equipment and refine the operational efficiency of lunar construction activities， this investigation delves into the application of the discrete element method （DEM） within the realm of lunar regolith contact mechanics. By harnessing the power of DEM， the primary objective is to provide not only theoretical insights but also practical and technical assistance for the meticulous planning and execution of future lunar base construction initiatives. Through the judicious application of DEM， it is envisaged that a robust framework can be established to guide and facilitate the successful realization of lunar base construction projects， thereby advancing humanity's exploration and utilization of extraterrestrial resources. It is crucial to acknowledge the immense challenges posed by lunar construction activities， where the understanding of lunar regolith behavior is paramount. By unraveling the complex interplay between lunar surface equipment and the dynamic lunar regolith， this investigation seeks to shed light on novel methodologies for optimizing construction operations on the lunar surface. The application of DEM offers a unique opportunity to simulate and analyze the intricate interactions between lunar regolith particles and construction equipment， providing valuable insights into the design and deployment of future lunar infrastructure.

Progress This research draws from a range of on-site lunar construction missions， including geological exploration， resource extraction and transport， and construction work， to analyze the application of the discrete element method （DEM） to the mechanics of lunar surface construction. Initially， the study critically examines the complex dynamics behind lunar weathering layer modelling and parameter calibration， elucidates methods for weathering layer modelling， and analyzes various particle contact models for different application scenarios， while summarizing effective methods for lunar weathering layer parameter calibration.In addition， this study delves into existing research to elucidate the complex interactions between lunar surface equipment and the lunar weathering layer. In the context of lunar soil collection， the study analyzes interactions such as drilling and shoveling，and investigates the effects of drilling and shoveling equipment structure and operating parameters on lunar soil collection performance from a DEM microscopic perspective. It also explores wheel rock and foot rock interactions to enhance lunar rover maneuverability and lander stability to ensure effective execution of lunar surface construction operations. Through careful exploration of these simulations， the study elucidates the underlying mechanics and dynamics that control these interactions， thereby enhancing the understanding and optimization of lunar construction methods. In addition， the study comprehensively analyzes the inherent carrying capacity of the lunar base， using the analytical power of the DEM to reveal the stability of the lunar habitat.This multifaceted exploration aims to provide valuable academic insights and practical guidance for the seamless advancement of lunar exploration efforts and the sustainable establishment of lunar infrastructure.

Conclusions and Prospects It is proposed that DEM can account for the microstructure and deformation of particulate materials such as water ice， including factors such as the shape， size， and arrangement of the particles. This enables DEM to more accurately simulate the deformation， damage and other behaviors of water ice under external forces. DEM cannot only simulate the mechanical behavior of granular materials， but also simulate the interaction between particles and fluids in multiphase fluid systems by combining with fluid dynamics methods. For particulate materials such as water ice， DEM can simulate interactions with liquid or gaseous media， such as the processes of particle deposition， suspension， and flow， etc. It can also be used to study the heat conduction behavior in the particulate system and the structural stability during the heating process， which is conducive to the optimization of the strategies and methods for water ice acquisition to support the lunar surface construction mission. In addition，when facing more complex unstructured terrain construction tasks， the terrain adaptability and obstacle-climbing ability of the foot-mounted lunar rover are more prominent. However， due to the complex mechanical control of the foot-mounted lunar rover， coupling simulation between DEM and dynamics is difficult， and the construction cost of unstructured terrain DEM models on the lunar surface is high. Therefore， improving the coupling performance of DEM and dynamics and enhancing the accuracy of macro-scale lunar soil DEM modeling are the challenges that foot-mounted lunar rover DEM simulations need to overcome in the future. Furthermore， current DEM study of the bearing capacity of lunar foundations， which focuses on simulating the mechanical behavior of lunar soil， can serve as a basis for assessing the support capacity of lunar soil for buildings. In the future， the feasibility of construction under different terrain conditions can also be considered， which will help to formulate more refined building plans， select the most suitable areas and locations for construction， and guide the design and construction process of buildings and ensure their stability and safety.

Keywords：lunar construction； discrete element method； lunar soil collection； lunar-based equipment； bearing capacity

DOI：10.13732/j.issn.1008-5548.2024.04.003