Eliminating shrinkage in tension stiffening model of concrete beams by the hybrid approach

摘要

This paper presents the methodology of shrinkage elimination in tension stiffening model for Reinforced Concrete (RC) flexural members based on the newly developed hybrid approach. Compared to the layered section model, the hybrid approach reduces multiple layers of concrete in the cross-section to two layers, one compressive and one tensile, each having homogenous deformation characteristics. The method combines the concepts of both the reinforcement-attributed and concrete-attributed tension stiffening approaches. To account for the shrinkage effect, the tension stiffening stresses is assumed acting at the consolidated area of tensile concrete. The hybrid approach is simple to apply and can readily be used by engineers in carrying out structural design. Formulations of the hybrid approach are derived in this paper, and numerical analysis of a RC beam specimen is performed to illustrate the application procedures.