Algorithmization and Application of Constitutive Equations for Modeling the Plane Stress State of Concrete

Modeling of concrete response using nonlinear constitutive equations is currently a very popular and promising field of science. Nowadays, there is already a number of different constitutive equations (material models) intended for concrete modeling in computational systems. These equations find their use mainly in the implicit or explicit finite element method and usually contain a lot of input parameters. However, the still inadequate exploration of this field of science provides the scope for algorithmization and application of other constitutive equations that can provide satisfactory results with relatively few input parameters. This fact is related to the goal of this paper that is algorithmization and application of constitutive equations intended for modeling the plane stress state of concrete. These equations are based on the incremental theory of plasticity in which some aspects such as yield function, hardening rule, non-associated flow rule, plastic hardening modulus, and equivalent stress and strain are applied. Algorithmization of constitutive equations is performed in Matlab and their application is focused on the tasks of uniaxial and biaxial compression of concrete for the purpose of demonstration of their capability to describe the concrete response in compression very satisfactorily.