Unit 6: Concrete (True-False)
True
Concrete containing rebar is known as reinforced concrete.
True
Concrete gardens because of chemical reaction called hydration that occurs between the water and cement in a concrete mixture.
True
Concrete has more compressive strength than lateral strength.
True
Concrete should normally be discharged from a concrete truck within 1 1/2 hr after water has been added to the mixture.
True
Fiber-reinforced concrete (FRC) is concrete reinforced with plastic or steel fibers, which minimize cracking and increase tensile strength.
True
Floor slabs are more difficult to cure than walls.
True
Forms for concrete walls should remain in place for three to seven days to allow sufficient time for curing.
True
Print specifications may give the types of admixtures for concrete.
False
Proportions of cement, aggregate, and water for concrete are consistent, regardless of the mix required.
True
Rebar is a deformed steel bar with ridges on the surface to allow the bars to interlock with concrete.
True
Rebar size and placement are shown on the plot plan.
True
Sand is the fine aggregate used in concrete mixtures.
False
The printreading abbreviation for face brick is FCB.
False
The process of manufacturing cement was developed by Joseph Portland.
False
Water with a pH of 6 to 8 is suitable for a concrete mixture. It's got to be close to 11.
True
When pouring foundation walls, concrete should be poured in lifts of 12" to 20".
