Effect of bond and corrosion within partial length on shear behaviour and load capacity of RC beam

This paper describes an experimental investigation into the effect of corrosion damaged partial length in one shear span on the shear behaviour and load capacity of reinforced concrete (RC) beams, where 14 RC beams were tested in four-point bending. Two shear span-to-effective depth ratios 2.0 and 3.0, two different partial lengths and three bond characteristics within the designed partial length were considered. Test results of the RC specimens were compared with theoretical results of the corresponding noncorroded bond-perfect RC beams, and the differences were analyzed to deduce the influence of the bond and corrosion within partial length on behaviour and load capacity of RC beams. The results indicate that the mechanical behaviour and load capacity of the test specimens are greatly influenced by the bond characteristics and high corrosion-induced damage within the partial length. Artificial elimination of the bond and neglecting of the corrosion-induced damage in the longitudinal bars and the connected stirrups within the partial length may lead to overestimate the residual capacity of the corrosion damaged RC beam. In assessing the residual life span and reliability of the in-service RC structures, it is very important to consider the severe corrosion damage within certain length of the RC elements.

Research highlights
► Effect of corrosion-damaged length in one shear span on the shear behaviour of RC beams was experimentally investigated.
► Artificial elimination of the bond and neglecting of the corrosion-reduced damage in the reinforcing bars may lead to improper conclusions.
► The severe corrosion and the sequential rupture of the stirrups must be considered in assessing the in-service RC structures.