FLEXURAL BEHAVIOR OF CORRODED REINFORCED CONCRETE BEAMS

Structural performance of corroded RC beams has been extensively studied, however, the relationships between residual load capacity (RLC) and corrosion degree do not agree well with each other in different literatures. In this paper, twelve artificial corroded beams and three natural corroded ones were tested, and results were compared with that of other researchers. Shown by the results, different anchorage conditions and consequent failure modes explain the large scatter of RLC at same corrosion degree. Under adequate anchorage, corroded beam acts as tied-arch and failed in typical flexure, unless serious corrosion can even cause rebar rupture. In such case, rebar section loss becomes the primary reason for RLC decrease, and bond deterioration becomes the main cause for stiffness degradation. Due to strongly nonuniform distribution of corrosion and fractional strain hardening of rebar, RLC and stiffness of natural corroded beams show relatively slighter decline. Finally, based on the above understanding a practical model is proposed to calculate RLC of corroded flexural members.