Cam CapModels for Lunar Soil: A First Look

摘要

The shearing behavior of a Lunar soil can be described by a Cam yield envelope with best-fitting parameters of friction angle (for critical state, constant-volume shearing) of 40° and critical pressure (compactional strength) of 0.22 MPa. At lower confining pressure, shearing at angles of friction > 40° is dilational, whereas shearing at confining pressures greater than about 0.1 MPa produces compactional flow with negative dilation angles. Lunar soils have large shear strength, due to irregularly shaped particles, and small compactional strength, due to small particle strengths. More accurate determination of the yield envelopes requires laboratory testing of Lunar soils and measurement of the volumetric strains.