Abstract：Based on the viewpoint of interaction between volumetric and shear strains in plastic deformation for rock and soil，the elastoplastic constitutive model for remolded clay under reduced triaxial compression(RTC) path has been established by using the numerical modeling method，which provides a practicable constitutive equation for computer simulation of excavation works. The three-dimensional deformation curved faces of volumetric and shear strains under the stress paths of conventional triaxial compression(CTC) and RTC in the whole stress field (p，q) are respectively presented through visualization. Comparing the two kinds of curved faces，it is found that there are obvious differences in slope between the two faces of shear strain，especially，the values of the volumetric strain for RTC are all negative，which means that the volume expansion appears in the whole deformation process. In addition，it has been found by comparing the two families of shear and volumetric yield loci under CTC and RTC paths that the differences in the basic trends of variation between the two families of shear yield loci are not large，but the shear strains under RTC path rise rapidly. The volumetric yield loci under CTC path firstly turns right slightly，then turns left slowly，however. The volumetric yield loci under RTC path turns left monotonously. These results further demonstrate that the influence of stress path on the constitutive relations is serious，especially the differences between the effects of the two stress paths，in which p increases and decreases respectively，are considerably large and can not be neglected.
