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1. Which type of cement is most commonly used in standard concrete
construction?
A. Type II
B. Type III
C. Type I
D. Type V
Type I is the general-purpose Portland cement used for most concrete applications
unless special conditions require otherwise.
2. The primary purpose of air-entrainment in concrete is to:
A. Increase compressive strength
B. Reduce setting time
C. Improve freeze–thaw resistance
D. Increase density
Air-entrained concrete creates tiny air bubbles that provide space for water to
expand during freezing, reducing cracking.
3. What is the maximum allowable slump for concrete used in footings,
according to ACI standards?
A. 8 inches
B. 2 inches
,C. 10 inches
D. 3 inches
Concrete for footings typically requires a low slump (about 3 inches) to ensure
stability and reduce segregation.
4. Which reinforcing steel grade is most common in structural concrete?
A. Grade 40
B. Grade 60
C. Grade 80
D. Grade 100
Grade 60 reinforcing steel (60,000 psi yield strength) is widely used in structural
applications.
5. What is the minimum curing period recommended for normal Portland
cement concrete at 50°F?
A. 3 days
B. 7 days
C. 14 days
D. 21 days
ACI recommends curing normal concrete for at least 7 days to achieve strength
and durability.
6. What is the purpose of control joints in concrete slabs?
A. Improve finishing
B. Provide drainage
C. Control cracking from shrinkage
D. Reduce curing time
Control joints allow cracks to occur in a controlled, straight line rather than
randomly across the slab.
, 7. In Nevada, which agency regulates contractor licensing, including the C-5
classification?
A. OSHA
B. ICC
C. Nevada State Contractors Board (NSCB)
D. ACI
The NSCB issues licenses and regulates contractor classifications including C-5
Concrete Contractor.
8. What is the typical minimum concrete cover over reinforcing bars in slabs
exposed to weather?
A. ½ inch
B. ¾ inch
C. 1 inch
D. 1½ inches
ACI code specifies 1½ inches cover for bars in slabs exposed to weather to protect
against corrosion.
9. Which test is commonly used to determine concrete compressive strength?
A. Schmidt rebound hammer
B. Cylinder break test
C. Ultrasonic pulse velocity
D. Core drilling
Concrete cylinders are cured and tested under compression to determine
compressive strength.
10. When placing concrete in hot Nevada conditions, what is the most critical
concern?
A. Slow set
B. High slump