Ground Technologies for Surface Operation Risk Mitigation

Unprepared lunar site surface regolith mechanics poses a significant operational risk in the development and sustainability of lunar infrastructure. Heavy loads, constant or transient, can affect the stability of the regolith and might cause stresses that are higher than the regolith yield strength, resulting in undesired regolith movement or bearing capacity failures. A geocell concept is proposed to lower the risks to future Lunar and Martian infrastructure that is associated with regolith surfaces that may be unstable under static and dynamic loads. Geocell or cellular confinement has been used for terrestrial applications with a high degree of success in enhancing the soil lateral and longitudinal strength for a variety of conditions. In this Phase I project, CFD Research Corp will demonstrate the feasibility of using geocells for ground stabilization using a combination of simulations and experimental tests at University of Illinois Urbana Champaign. The utility of geocell structures in assisting the regolith ground layers in resisting erosion, destabilization and trafficability of ground operation paths will be assessed and the sizing and spatial frequency of geocell structure placement will be estimated. Phase I will focus on demonstrating the benefits of geocell structures for landing area applications where plume-surface interactions (PSI) induce a complex transient load that can result in extreme erosion and bearing failure. In Phase II, the team will refine the geocell design and evaluation process for a wide variety of applications and configurations with a focus on prototyping and manufacturing, and will develop a comprehensive surface-operation plan for making effective use of regolith reinforcement structures.