Modeling of reinforced concrete membrane behavior considering shear stress transfer across cracks

In this study, a previously developed reinforced concrete panel (membrane) model formulation is improved by incorporating simple yet effective constitutive relationships that simulate shear transfer mechanisms across cracks. First, a friction-based shear aggregate interlock mechanism with cyclic degradation parameters is incorporated. Second improvement is the implementation of an origin-oriented dowel action model on reinforcing bars with cyclic degradation parameters. These mechanical enhancements are aimed to achieve better simulation of test results with consideration of physical phenomenon's (e.g. friction along cracks, dowel action, degradation) that are neglected (in full or partially) in the formulations of other panel models available in the literature. Improved model is further validated against test results from two different experimental programs. Sensitivity of the improved model to the coefficient of friction is evaluated through computational analyses carried out on five different panel specimens that are identified as sensitive to the applied shear transfer mechanisms due to their design or loading characteristics (e.g. asymmetric or inclined reinforcement, complicated loading conditions). Thereafter, using optimal friction coefficients obtained by the parametric sensitivity analysis results, global and local response predictions of the model for ten different panel specimens (including specimens used for sensitivity analyses) are compared with test results from two different experimental programs for validation of the improved model. Finally, it was observed that the improved panel model provides good correlation with test results as majority of the results are indeed satisfactory.