11.4. Mechanisms of Durability Loss

Try these first

1. 1.

   What occurs during carbonation in concrete?

   Hint

   Think about what CO₂ can do chemically.

2. 2.

   What does chloride ingress lead to?

   Hint

   What happens when metal rusts?

3. 3.

   What is carbonation in concrete?

   • A chemical attack
   • A physical process
   • A thermal reaction

   Hint

   Remember the interaction with CO₂.

4. 4.

   True or False: Chloride ingress is helpful for concrete.

   • True
   • False

   Hint

   Consider what happens when chloride meets steel.

5. 5.

   Evaluate a hypothetical concrete structure exposed to marine conditions. Predict how carbonation and chloride ingress will affect its durability over a 10-year period.

   Hint

   Consider both processes and think about their compounding effects.

6. 6.

   Design a concrete mix that minimizes the effects of sulfate attack. Outline the specific components to use and the rationale behind your choices.

   Hint

   What materials offer resistance against aggressive ions?