Degradation of dynamic bond-slip behaviors of corroded reinforced concrete: experimental study

Reinforced concrete structures exposed to marine environment throughout their design life often sustain high levels of deterioration due to corrosion of reinforcement. This causes large losses in cross-section and diminished bond performance resulting in reduced performance under seismic and everyday loading. This paper assesses the cyclic bond performance of corroded reinforcing through experimental studies. Tests were carried out to evaluate the degradation of dynamic bond-slip relationship of different corrosion levels. A series of 30 specimens with various corrosion levels of rebar and stirrup were designed and manufactured in this study. The specimen was cast as concrete cube with the dimension of 200mm, and a steel re bar was centrally embedded with two stirrups around. By using the accelerated corrosion method, the embedded steel rebar and stirrups were corroded using an electrochemical accelerated corrosion technique. Then cyclic loading test on the different corroded level specimens were carried out; the effects of different corrosion levels of rebar and stirrup on degradation dynamic bond behavior were studied. The observed crack opening and length with stirrup corrosion levels and dynamic bond behavior were further discussed.