Bifurcation analyses of finite/large deformation for a marble

The plastic dilatable constitutive relationship of finite/large deformation theory is used in present paper to analyze anti symmetric deformation of a marble. The stress formula, the eigenvalue equation and the condition that shear bands generate are obtained. In analyses of bifurcation behavior of a marble, it could be concluded that:(1)Under high confining pressures, angles of shear bands and the minimum critical stress of bifurcation are consistent well with those in experiments, while there are evident differences under low confining pressures, which shows the method is suitable for ductile material;(2) The method describes well the behaviors of marble before peak, but not after peak, which shows there probably are recursive bifurcations, such as secondary bifurcation, etc.