Triaxial A -value versus Swell or Collapse for Compacted Soil

The purpose of this technical note is to compare the triaxial A -value with the percentage of swell or collapse measured in the oedometer apparatus for three different compacted soils. Those soils that collapsed in the oedometer apparatus had a high A -value from the triaxial test that is indicative of contractive behavior, and those soils that tended to swell conversely had a low to negative A -value from the triaxial test indicative of dilative behavior. The relationship between triaxial A -values and the swell or collapse from oedometer tests may be useful in identifying soil-behavior discrepancies and laboratory testing errors. The soil behavior is independent of the dry density of the compacted soil and the confining pressure.