Simplified analytical model for flexural response of external R.C. frames with smooth rebars

In this paper an analytical model in a closed form able to reproduce the monotonic flexural response of external RC beam-column joints with smooth rebars is presented. The column is subjected to a constant vertical load and the beam to a monotonically increasing lateral force applied at the tip. The model is based on the flexural behavior of the beam and the column determined adopting a concentrated plasticity hinge model including slippage of the main reinforcing bars of the beam. A simplified bilinear moment-axial force domain is assumed to derive the ultimate moment associated with the design axial force. For the joint, a simple truss model is adopted to predict shear strength and panel …

Analisi teorico-sperimentale del comportamento di elementi in cemento armato soggetti a corrosione

Flexural behavior of corroded RC beams

Synopsis: A handily model to evaluate the bending resistance and the ductility of corroded beams critical in flexure and shear is proposed and debated. Effects of diffused and pitting corrosion on steel bars, compressive concrete strength reduction and concrete bond strength reduction due to rust creation are modelled. Practical method derived on limit state theory was here used to calculate the flexural and shear strength and the available ductility. The effectiveness of the model was also corroborated against numerous results collected in the literature pertaining to bending and shear resistance.

Shear and flexural strength of corroded R.C. beams

Simplified equations aimed at evaluating the flexural and shear capacity of corroded R.C. beams are presented and discussed in this paper, with reference to ordinary beams reinforced both longitudinally (with same-size bars) and transversely (with stirrups). A model is developed to take care of diffused and localised corrosion (pitting corrosion), concrete decay in compression and bond-strength decay at concrete-reinforcement interface. A fairly innovative contribution of this study is the introduction into the proposed equations of the main parameters governing the corrosion processes. The proposed approach is simple and effective, and may be adopted in the assessment of many damaged struc…