P. Pivonka, H.A. Mang:
"A 3D-Constitutive Model for Concrete Subjected to High Compressive Stress States";
in: "Proceedings of the 4th International Conference on Constitutive Laws for Engineering Materials", Rensselaer Polytechnic Institute, Troy, NY, USA, 1999, 395 - 398.
This paper deals with the development of a 3D-constitutive model for concrete subjected to high compressive stress states. The Leon model, previously formulated as a single surface model by Etse [1992], has been extended to account for high compressive stress states. The model is formulated within the theory of isotropic elasto-plasticity. It accounts for the dependence of concrete failure on the Lode angle $\theta$. A non-associative flow rule is used. The ductile behavior of concrete is modelled by a ductility function proposed by Etse, which is reformulated to account for high compressive stress states. Softening is considered on the basis of the fracture energy concept. Consistent linearization leads to a quadratic rate of convergence in the equilibrium iteration as part of incremental Finite Element analysis. The predective capabilities of the model are demonstrated numerically.[1992] G. Etse, Theoretische und numerische Untersuchung zum diffusen und lokalisierten Versagen in Beton. PhD theses, Universität Karlsruhe, Karlsruhe, Germany, In German.