木元 小百合

The aim of the present paper is to study strain localization problem of water-saturated clay using an elasto-viscoplastic model that is applicable to both normally and orverconsolidated clays. First, instability of the model under undrained creep conditions was analyzed in the sense of acceleration creep failure. Instability analysis shows that overconsolidated clay with positive dilatancy is more unstable compared with the normally consolidated clay with negative dilatancy. Then, finite element analysis of deformation of water saturated clay is presented under plane strain conditions. Numerical results is consistent with the non-linear instability analysis.

In the present paper, effect of dilatancy on strain localization was numerically studied for dilatant and contractant clays using a newly developed elasto-viscoplastic constitutive model which can be applied to both normally and overconsolidated clays. From the present numerical analysis, it was found that dilatancy characteristics plays an important role in the strain localization behavior.