The strain comprehensive structure potential (strain-CSP) is a new structural parameter of soils and it can be applied to complex stress condition conveniently. Based on the definition of strain-CSP

the structural parameter curves of intact loess or men-made structural loess are obtained using the data of stress-strain curves obtained from triaxial tests on intact loess (or men-made structural loess)，disturbed loess and saturated loess

and structural variation properties of unsaturated loess are analyzed under triaxial complex stress conditions. The results have shown that the strain-CSP as a new structural parameter of soils

its changing trend relative to a certain affecting factor is the same as that of the stress comprehensive structure potential. Using this new structural parameter of soils

the fundamental features of soils structural parameter curves under triaxial complex stress condition can be explained reasonably

and the variation and development of soils structural characteristics in 3-D complex stress state can be described suitably.