TY - JOUR
T1 - Influence of crack width, cover depth and concrete quality on corrosion of steel in HPC containing corrosion inhibiting admixtures and fly ash
AU - Lopez-Calvo, H. Z.
AU - Montes-García, P.
AU - Jiménez-Quero, V. G.
AU - Gómez-Barranco, H.
AU - Bremner, T. W.
AU - Thomas, M. D.A.
N1 - Publisher Copyright:
© 2018 Elsevier Ltd
PY - 2018/4
Y1 - 2018/4
N2 - In this study the influence of crack width, cover depth and concrete quality on corrosion of steel in high performance concrete was investigated. Three mixtures, one control and two more containing corrosion inhibiting admixtures, Calcium Nitrite and Disodium Tetrapropenyl Succinate, in combination with 20% fly ash replacement with respect to the cement weight were prepared. Specimens were concrete cylinders measuring 100 mm in diameter and 65 and 105 mm in length, with a 16-mm steel bar centrally placed at two concrete covers of 25 and 45 mm. Before being exposed to a simulated marine environment, the specimens were pre-cracked under a controlled splitting test with crack widths ranging from 90 to 330 μm formed perpendicularly to the reinforcing bars. During a 16-month exposure, the corrosion risk of the reinforcing bars was evaluated by half-cell corrosion potentials and the corrosion rate by linear polarization method. Also, the total integrated corrosion current was estimated. Results show that, albeit to different degrees, cracking was found to be an influencing factor in promoting corrosion of the steel in concrete with either 25 mm or 45 mm concrete cover; nevertheless, the effectiveness of the concrete cover depended greatly on the crack thickness. Results also revealed that corrosion inhibitors and fly ash were effective in delaying corrosion even in cracked concrete.
AB - In this study the influence of crack width, cover depth and concrete quality on corrosion of steel in high performance concrete was investigated. Three mixtures, one control and two more containing corrosion inhibiting admixtures, Calcium Nitrite and Disodium Tetrapropenyl Succinate, in combination with 20% fly ash replacement with respect to the cement weight were prepared. Specimens were concrete cylinders measuring 100 mm in diameter and 65 and 105 mm in length, with a 16-mm steel bar centrally placed at two concrete covers of 25 and 45 mm. Before being exposed to a simulated marine environment, the specimens were pre-cracked under a controlled splitting test with crack widths ranging from 90 to 330 μm formed perpendicularly to the reinforcing bars. During a 16-month exposure, the corrosion risk of the reinforcing bars was evaluated by half-cell corrosion potentials and the corrosion rate by linear polarization method. Also, the total integrated corrosion current was estimated. Results show that, albeit to different degrees, cracking was found to be an influencing factor in promoting corrosion of the steel in concrete with either 25 mm or 45 mm concrete cover; nevertheless, the effectiveness of the concrete cover depended greatly on the crack thickness. Results also revealed that corrosion inhibitors and fly ash were effective in delaying corrosion even in cracked concrete.
KW - Corrosion inhibitor
KW - Corrosion performance
KW - Cover depth
KW - Crack width
KW - Fly ash
UR - http://www.scopus.com/inward/record.url?scp=85043529779&partnerID=8YFLogxK
U2 - 10.1016/j.cemconcomp.2018.01.016
DO - 10.1016/j.cemconcomp.2018.01.016
M3 - Artículo
SN - 0958-9465
VL - 88
SP - 200
EP - 210
JO - Cement and Concrete Composites
JF - Cement and Concrete Composites
ER -