4.5. Shrinkage Cracking: Mechanism and Risk Areas

Try these first

1. 1.

   Define shrinkage in the context of concrete.

   Hint

   Think about how drying affects concrete.

2. 2.

   What is restraint in relation to concrete shrinkage?

   Hint

   Consider external and internal forces.

3. 3.

   What causes shrinkage cracks in concrete?

   • Moisture gain
   • Moisture loss
   • Chemical reaction

   Hint

   Think about what happens when concrete dries.

4. 4.

   T/F: All cracks in concrete are due to shrinkage.

   • True
   • False

   Hint

   Consider other failure mechanisms.

5. 5.

   A contractor is building a long retaining wall. Describe two potential risks of shrinkage cracking and suggest a mitigation strategy for each.

   Hint

   Think about environmental effects and preventive measures.

6. 6.

   Analyze the impact of a high water-cement ratio on shrinkage cracking risk in a concrete slab.

   Hint

   What happens when there's more water compared to cement?