5. Field Practices to Minimize Defects in Fresh Concrete

Try these first

1. 1.

   What is segregation in concrete?

   Hint

   Think about what happens to the aggregates in a non-uniform mix.

2. 2.

   Name one method to prevent segregation during transport.

   Hint

   Consider how you would transport a mix without shaking it.

3. 3.

   What is the main concern with segregation?

   • It creates a uniform mix
   • It leads to a non-uniform structure
   • It improves strength

   Hint

   Consider the consequences of poor mixing.

4. 4.

   True or False: Slump loss is a sign that concrete is becoming more workable.

   • True
   • False

   Hint

   Think about what happens to a mix as it sits.

5. 5.

   You are overseeing a concrete pouring project and notice slab stiffness starting to occur after 25 minutes. What steps should you take to ensure quality?

   Hint

   Think about what options are available for improving mix characteristics post-mixing.

6. 6.

   During transportation, segregation was observed in a concrete mix. Analyze the possible causes and suggest effective measures to prevent this in future projects.

   Hint

   Reflect on the impact of vibration and dropping heights in concrete handling.