Nonlinear Analysis of RC Members Using Plasticity with Multiple Failure Criteria

Concrete plasticity models for the analysis of reinforced-concrete (RC) members in plane stress are studied. The proposed plasticity model for reinforced concrete provides a unified approach combining plasticity theory and damage models. It addresses strength enhancement under multiaxial compression, and tensile cracking damage. The model uses multiple failure criteria for compressive crushing and tensile cracking. For tensile cracking behavior, rotating-crack and fixed-crack plasticity models are compared. As crushing failure criterion, the Drucker-Prager and von Mises models are used for comparison. The proposed model uses new and existing damage models for tension softening, tension stiffening, and compression softening due to tensile cracking. Finite-element analyses using the plasticity model are compared with existing experimental results. To verify the proposed crushing and cracking plasticity models, the experiments have load capacities governed either by compressive crushing of concrete or by yielding of reinforcing steel. The advantages and disadvantages of rotating-crack and fixed-crack plasticity models are discussed.