Durability of bridges in severe environments: The high quality cover plus monitoring-approach

During recent years several large concrete bridges and other structures have been built in marine and coastal environment with designed service life times of 100 years or even more. One problem of such structures is the achievement of a durable corrosion protection of the reinforcement in the areas exposed to chlorides from seawater or contaminated soils, especially in the splash water and spray water zones. Nowadays the following concept is often used to ensure durability: The quality of the concrete cover (thickness and diffusion resistance against chlorides) is designed and executed to provide sufficient protection and monitoring systems are used to verify the design assumptions.