Preliminary assessment on the effects of longitudinal cracks on carbonation-induced corrosion

Currently available models for reinforced concrete (RC) durability still lack the inclusion of the effects of cracks, which are inevitable in concrete structures, and literature on the effects of cracks on carbonation-induced corrosion is scarce, especially in case of cracks longitudinal to the reinforcement. This paper presents some preliminary experimental results on the effects of longitudinal micro-cracks on carbonation-induced corrosion, initiation and propagation phases. Experimental tests were performed to evaluate the penetration of carbonation, under accelerated conditions, in cracked and uncracked concrete made with different cement types and w/c ratios. Corrosion propagation was monitored, through electrochemical tech- niques, in longitudinally cracked and uncracked RC specimens subjected either to natural or accelerated carbonation. Results showed a more marked effect of the micro-crack on carbonation penetration in more impervious concretes, while the presence of the micro-crack did not seem to significantly affect corrosion propagation, except when developing to rebar depth.