Abstract
Galvanic anodes can supply corrosion protection current to steel by simply connecting them to steel in concrete and can prevent corrosion of steel for a long period. Furthermore, they are attracting interest because they do not require continuous monitoring nor other maintenance. Galvanic anodes are composed of a sacrificial metal, such as zinc, covered with backfills. The backfills contribute to a stable supply of corrosion protection current by maintaining the galvanic anode at a high alkaline level and by having high water retention. Their properties closely relate to the lifetime of the galvanic anode and its corrosion protection performance. Therefore, with the purpose of verifying the effect of backfill materials on the corrosion protection performance of galvanic anodes, we investigated the corrosion protection performance of galvanic anodes with three different backfills and without backfills on steel in chloride contaminated concrete. The results showed that the galvanic anodes with backfill exhibited higher corrosion protection performance, with larger values of depolarisation and corrosion protection current. It was also found that backfills affect the depolarisation and corrosion protection current, indicating that the corrosion protection performance of the galvanic anodes is affected greatly by the backfills. Furthermore, the influence of the external environment, such as temperature and humidity, was found to be different depending on which backfill is employed.
Keywords
galvanic anode, backfill material, corrosion protection current density, depolarisation amount.
DOI
10.5703/1288284318122
Recommended Citation
Ikeda, Hikaru; Kobayashi, Koichi; and Onoda, Motoki, "Effect of Backfills on the Corrosion Protection Performance of Galvanic Anode in RC Member" (2025). International Conference on Durability of Concrete Structures. 1.
https://docs.lib.purdue.edu/icdcs/2025/rrm/1
Effect of Backfills on the Corrosion Protection Performance of Galvanic Anode in RC Member
Galvanic anodes can supply corrosion protection current to steel by simply connecting them to steel in concrete and can prevent corrosion of steel for a long period. Furthermore, they are attracting interest because they do not require continuous monitoring nor other maintenance. Galvanic anodes are composed of a sacrificial metal, such as zinc, covered with backfills. The backfills contribute to a stable supply of corrosion protection current by maintaining the galvanic anode at a high alkaline level and by having high water retention. Their properties closely relate to the lifetime of the galvanic anode and its corrosion protection performance. Therefore, with the purpose of verifying the effect of backfill materials on the corrosion protection performance of galvanic anodes, we investigated the corrosion protection performance of galvanic anodes with three different backfills and without backfills on steel in chloride contaminated concrete. The results showed that the galvanic anodes with backfill exhibited higher corrosion protection performance, with larger values of depolarisation and corrosion protection current. It was also found that backfills affect the depolarisation and corrosion protection current, indicating that the corrosion protection performance of the galvanic anodes is affected greatly by the backfills. Furthermore, the influence of the external environment, such as temperature and humidity, was found to be different depending on which backfill is employed.
