Experimental study on effect of corrosion-induced cracking on bond property between deformed steel bar and concrete

摘要

In order to investigate the influences of cover cracking due to corrosion expansion on the bondrnbehaviour between the reinforcing bar and concrete, the pullout test on the bonding specimensrnwith deformed steel bar was designed. The strain gauges were fixed in the interior of deformedrnsteel bars. The accelerated corrosion tests by applying a constant electrical current to the bars by arnpower supply were used to compare the results that experienced in real RC structures. Thernreinforcement strains at various positions in bonding specimens with various corrosion-inducedrncracking widths are obtained. The present study analyzes the effect of corrosion cracking width onrnstrain of reinforcement at different positions. As a result, the bonding stresses at various positionsrnbetween the reinforcement and concrete are obtained. This paper also develops the relationshiprnbetween the corrosion cracking width and bonding stress between reinforcement and concrete.rnThe experimental results show that for the specimens with the narrow crack the peak bond stressrnmainly appears near region of the loading end，however for the specimens with the wide crack thernpeak bond stress is close to the free end.