Modified Mohr-Coulomb - Rankine material model for concrete

Purpose - The main aim of this paper is to present a three-dimensional numerical material model for concrete which combines plasticity with a classical orthotropic smeared crack formulation. A further aim is to raise a discussion leading to the creation of a comprehensive computer programme for the analyses of reinforced and prestressed concrete structures. Design/methodology/approach - A new numerical material model for concrete is developed and main theoretical explanations are given to aid in understanding the algorithm. The model is based on Mohr-Coulomb criterion for dominant compression and Rankine criterion for dominant tension influences. A multi-surface presentation of the model is implemented which permits the rapid convergence of the mathematical procedure. The model includes associated and non-associated flow rules, strain hardening and softening where the development of the plastic strain was described by the function of cohesion. Findings - Provides information about developing a new numerical material model for concrete. Practical implications - The model is implemented into the computer programme PRECON3D for the three-dimensional nonlinear analysis of the reinforced and prestressed concrete structures. Originality/value - In this model, the very complex behaviour of concrete is defined by elementary material parameters which can be obtained by a standard uniaxial test. The presented model enables a very detailed and precise analysis of reinforced and prestressed concrete structures until crushing with a high accuracy, so that the expensive experimental tests can be reduced. The paper could be very valuable to researchers in this field as a benchmark for their analyses.