Podcast
Questions and Answers
Which type of concrete must have a minimum strength of 15 MPa (2,200 psi)?
Which type of concrete must have a minimum strength of 15 MPa (2,200 psi)?
- Non-reinforced concrete
- Both non-reinforced and reinforced concrete (correct)
- Reinforced concrete
- Concrete for columns, fireplaces, chimneys and foundation walls
What is the minimum strength required for basement floors?
What is the minimum strength required for basement floors?
- 5-8% air entrainment
- 32 MPa (4,600 psi)
- 15 MPa (2,200 psi)
- 20 MPa (3,000 psi) (correct)
Why is air entrainment required for exterior applications?
Why is air entrainment required for exterior applications?
- To make concrete more workable and easier to place
- To reduce degradation caused by de-icing salts and exposure to freezing temperatures (correct)
- To protect the concrete in areas where soils are sulphate reactive
- To prevent volume increases and cracking in the concrete
Which test is used to gauge the consistency and workability of concrete?
Which test is used to gauge the consistency and workability of concrete?
What is ready-mix concrete?
What is ready-mix concrete?
What should the water and aggregate used for on-site mixing be free of?
What should the water and aggregate used for on-site mixing be free of?
What is the recommended water to cement ratio for garage and carport floors?
What is the recommended water to cement ratio for garage and carport floors?
Which temperature range requires concrete to cure for an additional three days?
Which temperature range requires concrete to cure for an additional three days?
What can be used to maintain moist conditions for curing when water curing is not practical?
What can be used to maintain moist conditions for curing when water curing is not practical?
What should be done to protect freshly placed concrete footings in freezing weather?
What should be done to protect freshly placed concrete footings in freezing weather?
What is a recommended way to reduce the quantity of wall and footing concrete on sloped sites?
What is a recommended way to reduce the quantity of wall and footing concrete on sloped sites?
