Construction Concrete and Masonry

Question 1

What is the standard water-to-cement ratio range for most structural concrete mixes?

Accepted Answer

0.45–0.60

Answer

0.20–0.30

Answer

0.35–0.45

Answer

0.65–0.75

Question 2

What is the purpose of rebar (reinforcing steel) in concrete?

Accepted Answer

To resist tensile stresses that concrete cannot handle

Answer

To increase concrete's compressive strength

Answer

To reduce the amount of cement needed

Answer

To speed up the curing process

Question 3

What is the minimum curing time for standard Portland cement concrete to achieve adequate strength?

Accepted Answer

7 days

Answer

1 day

Answer

3 days

Answer

28 days

Question 4

What does the designation 'f'c = 4000 psi' mean for concrete?

Accepted Answer

The specified compressive strength at 28 days is 4000 psi

Answer

The concrete weighs 4000 psi

Answer

The tensile strength is 4000 psi

Answer

The concrete must be placed at 4000 psi pressure

Question 5

What is the purpose of a slump test for concrete?

Accepted Answer

To measure the workability and consistency of fresh concrete

Answer

To measure concrete compressive strength

Answer

To determine aggregate size distribution

Answer

To check for air entrainment content

Question 6

What type of mortar joint is most water-resistant and recommended for exterior masonry?

Accepted Answer

Concave (tooled) joint

Answer

Struck joint

Answer

Raked joint

Answer

Flush joint