The Effect of Freezing‐Thawing and Wetting‐Drying Cycles on the Density and Bearing Power of Five Soils

S DENSITY is of major importance in engineerneering uses of soil from considerations of mechanical stability and of accessibility of the internal surface of the soil to water. For this reason soil structures, such as earth dams, subgrades, and bases of highways and airdromes, are usually compacted under rather rigid specifications to standards set up in accordance with results of laboratory tests. The ptfrpose of the investigation reported here was to obtain an idea on the extent to which the design densities and bearing power may be -expected to be maintained under service conditions involving freezing and thawing and wetting and drying cycles. SOILS EMPLOYED The soils employed.in this investigation are characterized in Table i. Only samples of the B horizon were used. The Missouri Hagerstown soil was obtained near Hannibal, Mo. The Hays soil was taken from the grounds of the Agricultural Experiment Station at Fort Hays, Kans. The Zaneis and Stephenville soils were taken from Stephens County near Duncan, Okla. The Nimitz fine sand was" obtained in Grady County near Rush Springs, Okla.