Numerically efficient mechanical modeling of reinforced concrete membrane elements with fixed, interlocked cracks

Abstract Compression field approaches such as the Cracked Membrane Model with fixed, interlocked cracks (CMM‐F) are efficient tools for the mechanical modeling of reinforced concrete elements, providing the mechanical model required for finite element analyses. This paper introduces a modification and extension of the CMM‐F that includes (i) dowel action contributing to the stress transfer across cracks, modeled using solutions for beams on elastic foundations, (ii) a novel method for calculating crack kinematics based on equilibrium and compatibility of a differential concrete element located between two cracks, and (iii) a simplified version of this method that enables efficient finite element implementation by avoiding iterative solution procedures without significantly compromising accuracy. The validation of the model against 31 published panel tests with varying reinforcement layouts, concrete strengths, and loading schemes shows a good agreement, both in terms of load–deformation behavior and ultimate state predictions. A sensitivity analysis demonstrates that the constitutive relationships and stress transfer models (i) have a negligible effect on the load–deformation behavior prior to yielding of the weaker reinforcement, and (ii) affect the response after yielding (including ultimate load and deformation capacity) only if the associated failure mechanisms become governing. Dowel action—even if accounted for in a conservative manner—can beneficially influence the shear resistance in cases of pronouncedly orthotropic reinforcement, as common, for example, in girders with much stronger longitudinal than transverse reinforcement.