16.2.4. Admixtures

Try these first

1. 1.

   What is an admixture in concrete?

   Hint

   Think about why we might need to improve concrete.

2. 2.

   Name one type of admixture.

   Hint

   Consider the functions they serve.

3. 3.

   What is the purpose of water reducers in concrete?

   • To add more water
   • To improve workability
   • To slow down setting time

   Hint

   They allow concrete to flow better.

4. 4.

   True or False: Air-entraining agents increase the risk of freeze-thaw damage.

   • True
   • False

   Hint

   Think about the protective role of air pockets.

5. 5.

   Consider a new project in a region with extreme cold. You are responsible for selecting admixtures to use in the concrete mix. Which admixtures would you choose and why?

   Hint

   Think about the environmental conditions and how they affect concrete.

6. 6.

   You're presented with a case where concrete is setting too quickly during a summer project, leading to cracking issues. Identify which admixture can be added to alleviate this problem and provide a rationale.

   Hint

   Recall the properties of retarders.