Grenzen des Korrosionsmonitorings zum Wirksamkeitsnachweis des Instandsetzungsprinzips 8.3 (W-Cl)

Corrosion monitoring within the repair principle 8.3 (W-Cl) in cracked, short term chloride exposed and subsequently coated reinforced concrete. Reinforcement Corrosion in cracked concrete due to de-icing salt exposure for a short period of time has been a well-known and controversially discussed problem in the maintenance of basic infrastructure for decades. For the preservation of these structures, technical, German guidelines offer the repair principle 8.3 (W-Cl). Here, the cracked reinforced concrete surface is provided with a surface protection system to prevent further entry of deleterious species and to achieve long-term drying of the concrete. We will show whether the already existing deleterious input in the form of chlorides from de-icing salts can reach a supercritical level within one winter period and which parameters can be used to determine the condition of the affected structure. The course of the corrosion currents. the course of the linear polarization resistances as well as the chloride concentration in the crack area at the reinforcement level are the most important parameters. The results show that only their correlation enables deterministic proof of the success of the repair. Without knowledge of these values, it is not possible to perform a reliable condition assessment and because of that continuous corrosion monitoring is indispensable.