OCR*-Based Geotechnical Screening Framework for Lunar Infrastructure
This work presents a construction-oriented geotechnical screening framework for evaluating and ranking candidate lunar landing and infrastructure sites using a first-order mechanics-based interpretation of the available lunar ground data. Rather than treating the Moon as a geological mapping problem, the framework translates observations from the Apollo, Luna, and recent Chang'e missions into engineering information that can support early infrastructure planning.
 
At the core of the methodology is OCR*, a relative mechanical descriptor that integrates multiple independent observations, including penetration resistance, density and porosity trends, returned sample characteristics, surface interaction, and documented soil mechanics behavior, to estimate the relative mechanical state of the regolith. OCR* is not a direct measurement of overconsolidation ratio, strength, bearing capacity, or settlement; instead, it provides an engineering interpretation of how the regolith is expected to behave during construction.
 
The interpreted OCR* values are subsequently translated into the Lunar Regolith Classification (LRC), a construction-oriented classification system describing the expected mechanical condition of the regolith. Rather than representing geological layers, the LRC classes describe relative engineering behavior ranging from loose, disturbance-sensitive materials to dense regolith and eventual rockmass interaction. The classification provides a common engineering language for discussing constructability during the conceptual design stage.
 
Using this framework, each candidate landing site is evaluated in terms of construction-related performance, including:
Relative excavation effort.
Expected foundation performance.
Construction trafficability.
Surface preparation requirements.
Ground improvement needs.
Relative engineering variability.
Overall infrastructure readiness.
 
The methodology is then applied to the Apollo and Luna landing sites to establish engineering calibration benchmarks before extending the interpretation to current Artemis IV candidate landing regions. Based on the interpreted mechanical state, spatial continuity of favorable terrain, and anticipated construction requirements, the framework identifies those areas that provide the most balanced combination of constructability and operational flexibility for early lunar infrastructure deployment.
 
Importantly, the framework is intended for preliminary engineering screening rather than engineering design. It does not replace engineering site investigations, in-situ testing, laboratory characterization, or project-specific geotechnical analyses. Instead, it provides a structured means of prioritizing candidate sites and identifying where future engineering investigations should be concentrated as lunar exploration transitions from scientific discovery toward sustained surface construction.