**44**, 3-4, pp. 445-469, 1996

### On Regularization of Plastic Flow Localization in a Soil Material

Density-dependent critical state line (Cam-Clay type) model is regularized by viscoplastic formulation to assure the mathematical well-posedness of the initial Cauchy problem. In computations this reduces the so-called *Primary Mesh Dependence* which is defined in the paper. Several numerical examples of two-dimensional plane strain pillar problem confirm the validity of the proposed formulation and its usefulness in numerical calculations.

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