Paper presents results of FE modelling of failure behaviour of reinforced concrete columns under eccentric compression. Concrete was described with an elasto-plastic model using isotropic hardening and softening. A Drucker-Prager criterion with a nonassociated flow rule was defined in a compressive regime and a Rankine criterion with an associated flow rule adopted in a tensile regime. To ensure the mesh-independence and to capture strain localization in concrete, both criteria were extended by a characteristic length of microstructure in a softening regime with the aid of a non-local theory. The reinforcement was described with an elastic-ideally plastic constitutive law by von Mises. Two-dimensional plane strain and three-dimensional simulations were performed. The FE-calculations were carried out with a different characteristic length of micro-structure, reinforcement ratio, column slenderness, load eccentricity, distribution of the tensile strength, bond-slip between concrete and reinforcement and fracture energy. The FE results were quantitatively compared with those from laboratory experiments performed by Kim and Yang [Kim J, Yang J. Buckling behaviour of slender high-strength concrete columns. Engineering Structures 1995;17(1):39-51]. A satisfactory agreement was achieved.
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