The assessment of concrete structures affected by corrosion deterioration is a critical challenge in structural engineering, as preventing sudden failures is essential to avoid severe human and economic consequences. This study presents the results of an experimental campaign on full-scale, pretensioned prestressed concrete (PC) beams without transverse reinforcement, which were naturally exposed for over ten years to cyclic wetting with marine water, leading to significant corrosion damage induced by chlorides. The work aims to investigate the shear performance of such PC beams deteriorated by corrosion and subsequently subjected to repairing interventions, by means of three-point bending tests. A comprehensive diagnostic approach was employed: (1) visual inspections were performed along the beam length to detect surface damage induced by corrosion; (2) electrochemical measurements were conducted — including corrosion potential, electrical resistivity, chloride content, and corrosion rate — to map the longitudinal distribution of corrosion and to assess the correlation between surface defects and internal degradation; (3) the damaged regions of the beams were patch-repaired by using mortar to restore bond between strands and concrete; (4) the shear capacity was evaluated through three-point bending tests, with the results further examined by using the Digital Image Correlation and the saw-cut method was also adopted for the estimation of the residual prestress level; (5) prestressing strands were retrieved and analysed using the laser scanner technique, enabling the 3D reconstruction of the corrosion morphology and allowing the mapping of pit locations and severity along the beam length. The collected dataset highlights: (1) the critical importance of advanced diagnostic and monitoring techniques for the reliable assessment of existing corroded structures and for the correlation of data; (2) the dependency of the residual capacity of corroded PC beams on patch-repairing interventions, highlighting the particular care that must be paid to optimise the maintenance strategy of existing PC members.
Experimental study on the shear behaviour of naturally corroded prestressed concrete beams without transverse reinforcement: from diagnosis to post-repair performance / Sirico, A., Palii, O., Belletti, B., Ravasini, S., Sanchez Montero, J., Torres, J.. - In: CONSTRUCTION AND BUILDING MATERIALS. - ISSN 0950-0618. - 535:(2026). [10.1016/j.conbuildmat.2026.146385]
Experimental study on the shear behaviour of naturally corroded prestressed concrete beams without transverse reinforcement: from diagnosis to post-repair performance
Sirico A.
;Palii O.;Belletti B.;Ravasini S.;
2026-01-01
Abstract
The assessment of concrete structures affected by corrosion deterioration is a critical challenge in structural engineering, as preventing sudden failures is essential to avoid severe human and economic consequences. This study presents the results of an experimental campaign on full-scale, pretensioned prestressed concrete (PC) beams without transverse reinforcement, which were naturally exposed for over ten years to cyclic wetting with marine water, leading to significant corrosion damage induced by chlorides. The work aims to investigate the shear performance of such PC beams deteriorated by corrosion and subsequently subjected to repairing interventions, by means of three-point bending tests. A comprehensive diagnostic approach was employed: (1) visual inspections were performed along the beam length to detect surface damage induced by corrosion; (2) electrochemical measurements were conducted — including corrosion potential, electrical resistivity, chloride content, and corrosion rate — to map the longitudinal distribution of corrosion and to assess the correlation between surface defects and internal degradation; (3) the damaged regions of the beams were patch-repaired by using mortar to restore bond between strands and concrete; (4) the shear capacity was evaluated through three-point bending tests, with the results further examined by using the Digital Image Correlation and the saw-cut method was also adopted for the estimation of the residual prestress level; (5) prestressing strands were retrieved and analysed using the laser scanner technique, enabling the 3D reconstruction of the corrosion morphology and allowing the mapping of pit locations and severity along the beam length. The collected dataset highlights: (1) the critical importance of advanced diagnostic and monitoring techniques for the reliable assessment of existing corroded structures and for the correlation of data; (2) the dependency of the residual capacity of corroded PC beams on patch-repairing interventions, highlighting the particular care that must be paid to optimise the maintenance strategy of existing PC members.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
