17.2.1. Environmental Conditions

Try these first

1. 1.

   What is freeze-thaw exposure?

   Hint

   Think about how temperature changes affect water.

2. 2.

   Name one way to prevent damage from freeze-thaw cycles.

   Hint

   Consider materials added to concrete mix.

3. 3.

   What does freeze-thaw exposure refer to?

   • Cycles of wet and dry weather
   • Cycles of freezing and thawing of water within concrete
   • High temperature conditions

   Hint

   Think about how water behaves when it freezes.

4. 4.

   Can sulfate presence cause expansion in concrete?

   • True
   • False

   Hint

   Recall the impact of chemical reactions on materials.

5. 5.

   Design a concrete mix for a pavement expected to endure severe freeze-thaw cycles based on your understanding of air-entraining agents and other additives.

   Hint

   Consider what materials would aid in freeze-thaw resistance.

6. 6.

   Evaluate how different sulfate levels might affect the mix design for concrete in a contaminated region. Discuss the implications of using regular versus sulfate-resistant cement.

   Hint

   Think about the chemistry behind cement interactions with sulfates.