6.1. Guidelines

Try these first

1. 1.

   What is a cold joint?

   Hint

   Think about what happens when new and old concrete meet.

2. 2.

   Why is proper compaction important?

   Hint

   Consider what might happen if air pockets were left in concrete.

3. 3.

   What is one of the main guidelines for placing concrete?

   • Place as far from final position as possible
   • Place in horizontal layers
   • Let it sit without compaction

   Hint

   Remember the recommended dimensions for the layers.

4. 4.

   True or False: Cold joints occur when new concrete is placed without following proper guidelines.

   • True
   • False

   Hint

   Think about how stopping and starting the pour affects concrete.

5. 5.

   A construction team placed concrete with significant delays due to sudden rain. What are the implications of this decision for the strength of the concrete structure?

   Hint

   Consider how time and moisture affect concrete's ability to cure.

6. 6.

   During a project, a worker dropped concrete from a height of 4 meters into formwork. Analyze the possible effects of this act on the final concrete strength.

   Hint

   Reflect on how the impact changes the mixture.