Mechanical Properties of Alluvium from Nellis Air Force Range, Nevada; Luke Bombing and Gunnery Range, Arizona; and White Sands Missile Range, New Mexico.

Mechanical properties of four types of alluvium were evaluated under cycled hydrostatic compression, cycled uniaxial strain, triaxial compression, and controlled strain path loading conditions. The materials that were tested consisted of remolded soil similar to that found in portions of Nellis Air Force Range, Nevada, undisturbed soil core from the DIRECT COURSE test site at the White Sands Missile Range, New Mexico, and both remolded soil and undisturbed soil core from the CARES-Dry test site at the Luke Bombing and Gunnery Range, Arizona. The remolded samples were compacted to a specified density of 1.9 gcu em at a specified moisture content of 6 percent by weight. These samples consistently showed evidence of achieving full saturation at mean normal stresses of 100 to 200 MPa. The undisturbed CARES-Dry cores had lower moisture contents and the undisturbed DIRECT COURSE cores had higher void ratios indicated by lower sample densities and neither materials showed signs of achieving full saturation during the tests. Material behavior is therefore critically dependent on dry density and air voids within pressure regimes tested, and these factors should be evaluated before selection of material properties for modeling. Keywords Mechanical properties, Alluvium, Strain path tests, Uniaxial strain, Triaxial compression, and Hydrostatic compression.