Reinforced concrete structures durability
**Service Life Assessment of Reinforced Concrete Structures:**
– Tuutti model for service life assessment
– Variables influencing service life
– Initiation and propagation periods of steel rebar corrosion
– Identification of initiation time and propagation time
– Factors affecting initiation time: carbonation, chlorides
**Corrosion Mechanisms in Reinforced Concrete Structures:**
– Carbonation-induced corrosion:
– Rate of carbonation propagation
– Factors affecting carbonation rate
– Evaluation of initiation time using carbonation coefficient
– Chloride-induced corrosion:
– Localized corrosion due to chlorides
– Factors influencing initiation time
– Transport phenomena of chloride penetration
– Chloride binding in concrete
**Concrete Cover and Corrosion Protection:**
– Concrete cover cracking as a limit state
– Factors affecting corrosion rate: oxygen, water content, humidity
– Steel rebar protection in an alkaline environment
– Importance of maintaining passivation condition
**Durability Design Approaches:**
– Standard approach (EN 206):
– Identification of exposure conditions and degradation process
– Prescriptions for w/c ratio, cement content, cover thickness
– Performance-based approach:
– Real design based on degradation process models
– Consideration of environmental factors as loads
**References and Further Reading:**
– Key references on material degradation, corrosion, and durability
– European projects like DuraCrete and FIB Model Code for Service Life Design
– Concrete degradation and reinforced concrete as related topics.https://en.wikipedia.org/wiki/Reinforced_concrete_structures_durability