Damage-plasticity modeling of shear failure in reinforced concrete structures

Shear failure is an important design consideration for reinforced concrete structural components. Therefore much attention has been drawn to the development of theoretical and computational models for characterizing its complex and progressive nature. This paper establishes a damage -plasticity constitutive relationship for concrete through the introduction of a new stress decomposition procedure, referred to as shear-normal decomposition. The stress tensor is decomposed into a shear stress tensor representing the shear state and a normal stress tensor representing the tensile/compression state. The degradation of the mechanical performance of concrete is accounted for through shear, tension and compression damage variables. The shear stress-shear strain curve of concrete is calibrated by experiments and is rendered independent of the tensile and compressive stress-strain curves. The coupling between tension-shear and compression-shear are accounted for by the criterion for shear damage evolution. Several numerical examples are presented that illustrate the unique advantages of the proposed model.