Consolidation of Loess

Details

• Creators:
  Kane, Harrison
• Corporate Creators:
  University of Iowa
• Corporate Contributors:
  Iowa State Highway Commission
• Subject/TRT Terms:
  Collapse Properties Compression Tests Effective Stress Loess Pore Water Pressures Soil Consolidation Test Stress Ratio
• Publication/ Report Number:
  71-2, HR-144
• Resource Type:
  Tech Report
• Geographical Coverage:
  Iowa ; United States
• Edition:
  Final Report
• Corporate Publisher:
  Iowa State Highway Commission
• Abstract:
  Effective stress paths for a loessial soil subject to collapse during confined compression have been determined from the results of a testing program consisting of (1) confined compression tests on natural samples of loess with initial water contents ranging from air-dry to saturation, (2) negative pore-water pressure measurements to -300 psi during these tests, and (3) K₀-tests in which the lateral stress ratio was measured for one-dimensional strain. Before collapse, coefficient of earth pressure at rest (K₀) was found to average 0.23, an extremely low value for a loose soil, whereas after collapse, K₀ increased to 0.54, which is consistent with values for other soils. Because of the low K₀-values before collapse, the effective stress path for loading in confined compression initially approaches the failure envelope. At collapse the stress path intersects the failure envelope and thereafter it changes direction as a consequence of the higher K₀-value after collapse. From the stress path interpretation of the results, it is demonstrated that the collapse mechanism of loess in confined compression and during wetting is a shear phenomenon and subject to analysis in terms of effective stresses.
• Format:
  PDF
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha256:0a295b6275de0cc51ad8d243c9cd261ecd1973f3632c4faf11125bb74c7a71cc
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/66663/dot_66663_DS1.pdf
• File Type:
  [PDF - 10.12 MB ]