Laboratory Characterization of Stress-Strain Behavior of Soils by Stress and/or Strain Path Loading

Strain path control during loading in addition to the often-desired stress path control is shown to constitute a versatile method of characterizing stress-strain response of soils in the laboratory. It allows probing stress or strain increments to be applied in any direction at an ambient effective stress state to study the stress history and stress-path-dependent response. The capture of even the potential strain softening and the post peak behavior is made possible with no difficulty. Some unique capabilities of a triaxial and a multiaxial hollow cylinder torsion apparatus of these types are demonstrated by results of tests on a saturated sand.