Act 6

Which of the following occurs in concrete due to cement hydration?

• Drying shrinkage

• Plastic shrinkage

• Creep

• Chemical shrinkage

Round aggregate is not beneficial for concrete workability.

• True

• False

F-1 concrete requires less air content than F-2 concrete.

• True

• False

Concrete A, Concrete B, Concrete C, and Concrete D have been prepared with a W/C ratio of 0.30, 0.40, 0.50, 0.60, respectively. Which concrete would exhibit the lowest degree of permeability?

• Concrete C

• Concrete B

• Concrete D

• Concrete A

Which of the following is considered to determine the approximate mixing water content of concrete for given nominal maximum size of aggregate?

• Slump

• Cement content

• Aggregate content

• Fineness modulus of sand

Which of the following is used in the levelling of fresh concrete?

• Bull float

• Screed

• Broom

• Trowel

Concrete A, Concrete B, Concrete C, and Concrete D are going to be produced with the same cement and aggregate contents but using the water content of 170, 180, 190, and 200 kg/m3, respectively. Which concrete will have the highest workability?

• Concrete A

• Concrete B

• Concrete C

• Concrete D

Which of the following curing methods would be the best for the strength development in concrete?

• Wet burlap covering

• Plastic sheet covering

• Sealing with impervious paper

• Sealing with curing compound

Which of the following properties is generally used in the quality control of concrete?

• Shrinkage

• Compressive strength

• Splitting tensile strength

• Flexural strength

Which of the following will be conducive to reducing the freeze-thaw damage of concrete?

• Inadequate air void system

• Higher degree of saturation

• Lower permeability

• Greater porosity