16.5.2. Mixing

Try these first

1. 1.

   What is the minimum time recommended for mixing concrete?

   Hint

   Think about how long you would want to mix to ensure everything is blended well.

2. 2.

   Explain why it is important to transport mixed concrete within 30-45 minutes.

   Hint

   Consider what happens to concrete after it has been mixed for a while.

3. 3.

   What is the minimum mixing time for concrete?

   • 60 seconds
   • 90 seconds
   • 120 seconds

   Hint

   Remember the discussion about uniformity in mixing.

4. 4.

   True or False: Concrete must be transported to the site within 30-45 minutes after mixing.

   • True
   • False

   Hint

   Think about the properties of concrete after mixing.

5. 5.

   You mix a batch of concrete for 80 seconds and transport it after 50 minutes. What issues are likely to arise from this scenario?

   Hint

   Think about how the properties of concrete change over time.

6. 6.

   Find the right balance for mixing concrete: If you were to specify a mixing time for a project, what factors would you need to consider?

   Hint

   Reflect on different mixing scenarios discussed.