Research Report 164 GEOMETRIC INTERPRETATION OF THE THREE-DIMENSIONAL YIELD CRITERION OF SOILS

摘要

A geometric interpretation of the invariants of a three-dimensional tensor is developed. With this interpretation, the yield criterion for three-dimensional plastic deformation is given geometric expression similar to the Coulomb criterion of yielding for plane plastic deformation. It is discovered that the procedure conventionally used in triaxial tests to determine the yield criterion is not theoretically valid. An alternative method based on the geometric interpretation developed herein is suggested.