Investigation on the effectiveness of the repair method 8.3 'Corrosion protection by increasing electrical resistivity' in chloride-containing concrete Part 1: Overview and recognition of Prof. Raupach's contribution

The repair method 8.3 “Corrosion protection by increasing the electrical resistance” according to EN 1504 (or the repair principle W-Cl according to the DAfStb directive “Protection and repair of concrete building materials”) represents a technically and economically interesting method for the repair of chloride-contaminated concrete components. The coating applied as part of the repair principle prevents further water absorption of the concrete and, due to its permeability to water vapor, allows the concrete to dehydrate. Over time, this leads to an increase in the electrolytic resistance and thus to a reduction in the rate of corrosion. The article deals with the basic principles underlying this repair principle, deals with the current regulatory situation, and shows the responsibility of the expert planner. Groundbreaking studies on the effectiveness of the repair principle were carried out by Prof. Raupach, to whom this article is dedicated, and are summarized in this paper. The objective of the new studies, which build on the aforementioned research, is to establish universally accepted application limits, for example, the level of the remaining chloride concentration, for the low-risk use of this repair method.