Behavior of Corroded Steel Reinforcing Bars Under Monotonic and Cyclic Loadings

Abstract

This paper investigates the monotonic and low-cycle fatigue properties of corroded steel reinforcing bars and compares their characteristics to that of un-corroded ones. Specifically, this paper investigates the effect of corrosion rate on the degradation of monotonic mechanical properties and low-cycle fatigue life of BS4449/2005 Grade B500B steel reinforcing bars. Twenty four samples of Grade B500B bars were corroded in the laboratory by immersing un-corroded steel bar samples in sealed flasks filled with a 10% concentration mixture of sulfuric and nitric acids as an accelerated corrosion substance. Three different corrosion levels were selected in this study, mainly 9–10%, 13–15%, and 19–20% measured as mass loss of un-corroded bar specimens. Monotonic tensile tests were carried out on 8 sample bars and 24 low-cycle fatigue tests were conducted at different strain amplitude mainly, ±4%, ±5% and ±6%. It is observed that the material's yield and ultimate tensile strengths and ductility, in addition to the fatigue life and the total dissipated energy of the steel bars, are reduced with increasing corrosion damage levels. Other conclusions and observations were also drawn.