LOESS SOILS IN SOUTHEASTERN WASHINGTON

The purpose of this note is to partially answer some questions regarding the nature of the undistrubed loess soils in the Palouse Hills in southeastern Washington and to delineate the general characteristics of the terrain and soils. The primary topics included are geology, permeability and consolidation, and shear strength. The loess soil layer in the region is the result of glacial accumulations in the Columbia drainage system being carried into eastern Washington by the prevailing southwest winds. This has occurred since the Pleistocene period and continues today at an even more rapid rate due to the soil's agriculture-related vulnerability to wind action. The prevailing winds produce modest upwind slopes and every steep downwind slopes with occasional earth slides being characteristic of the latter. The soil is characterized by high permeability and settlement rates. Shear strength have been represented for saturated conditions on local loess by a minimum cohesion of 200 psf (9,600 N/sq M) and a friction angle of 28 degrees.

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 00196152
  • Record Type: Publication
  • Report/Paper Numbers: ASCE 14621 Proceeding
  • Files: TRIS
  • Created Date: Oct 17 1979 12:00AM