A gradient-enhanced smeared crack model and bond-slip interface elements are utilized in finite element simulations of reinforced concrete. The crack model is rooted in an enhanced plasticity theory. It uses the Rankine failure surface dependent on an equivalent fracture strain measure as well as on its Laplacian. As a result, finitely sized fracture process zones and realistic crack spacings are obtained.
A reinforced concrete bar in uniaxial tension is analyzed to demonstrate the regularizing influence of the internal length parameter in the model and to evaluate the influence of the model parameters on the energy dissipation in multiple cracks. A comparison of numerical simulations with experimental results for a beam without shear reinforcement in four-point bending conditions concludes the analysis.
Higher-order continuum, finite element analysis, fracture localization, reinforced concrete, crack spacing.