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The effects of shrinkage variation within the beam depth and bending creep on the time-dependent flexural behavior of reinforced concrete (RC) beams were examined via two sets of experiments and numerical analyses. Each test set included four types of experiments: axial creep, beam shrinkage, bending creep, and time-dependent RC beam bending tests. The variations in beam shrinkage and bending creep strain were determined using the American Concrete Institute’s shrinkage and creep prediction models, respectively. Time-dependent finite-element beam equilibrium equations were presented using an incremental form of the age-dependent constitutive equation. The mathematical creep model of the constitutive equation accounted for the aging effects of the elastic modulus and the creep development under a multi-sequential loading condition with a single creep curve. The resulting finite-element formulation captured the mechanical and non-mechanical phenomena of the aging effect of concrete at an early age, shrinkage variations within the beam depth, and bending creep. Comparisons between the age-dependent responses of the measured and predicted results of the RC beam test specimens illustrated the significant effects of shrinkage variation and bending creep on the time-dependent behaviors of RC flexural members. |
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