Experimental correlations between crack opening and corrosion measurements in prestressed concrete beams

The assessment of concrete structures suffering corrosion deterioration represents nowadays one of the most crucial topics for the engineering community, in order to avoid sudden failures resulting in human losses and high financial damages. Within this framework, monitoring through in-situ inspections the conditions of existing reinforced concrete (RC) and prestressed concrete (PC) structures can represent a key tool for planning repairing and strengthening interventions. In this work, 10-year-old prestressed concrete beams subjected to natural chloride attack due to wet and dry cycles of seawater, have been experimentally investigated to estimate corrosion. Along their length, different measurements, such as potential, resistivity, chlorides content and corrosion rate have been performed to highlight the longitudinal corrosion pattern. Then, also concrete cover losses and crack openings were detected, to try to find a correspondence between surface defects and corrosion measures and to improve the knowledge of corrosion phenomenon in PC beams, considering the spatial variability.