AL CC Concrete Construction Contractor
Exam Practice Questions And Correct
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Rationales 2027 Q&A | Instant
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Q1. What is the primary purpose of properly proportioning a concrete
mix?
A. To eliminate the need for curing
B. To increase the amount of water in the mixture
C. To achieve the required strength, durability, workability, and economy
D. To prevent all shrinkage
Answer: C. To achieve the required strength, durability, workability, and
economy
Rationale: Proper mix proportioning balances cementitious materials,
water, aggregates, and admixtures to produce concrete with the required
performance characteristics.
,Q2. Which material primarily binds the aggregate particles together in
conventional concrete?
A. Fine aggregate
B. Cement paste
C. Coarse aggregate
D. Mixing water
Answer: B. Cement paste
Rationale: Cement paste, consisting primarily of cement and water,
hydrates and binds the aggregate particles into a hardened mass.
Q3. What is the water-cement ratio?
A. The ratio of aggregate to cement
B. The ratio of water weight to cementitious-material weight
C. The ratio of cement volume to aggregate volume
D. The ratio of fine aggregate to coarse aggregate
Answer: B. The ratio of water weight to cementitious-material weight
Rationale: The water-cement ratio is a major factor affecting concrete
strength, permeability, and durability.
Q4. Increasing the water-cement ratio generally has what effect on
hardened concrete?
,A. Increases strength
B. Decreases permeability
C. Decreases strength
D. Eliminates shrinkage
Answer: C. Decreases strength
Rationale: Excess mixing water creates additional capillary pores after
evaporation, generally reducing strength and increasing permeability.
Q5. What is the main purpose of aggregate in concrete?
A. To provide bulk and structural stability
B. To replace all cement
C. To eliminate curing
D. To increase water demand intentionally
Answer: A. To provide bulk and structural stability
Rationale: Aggregates make up most of the concrete volume and
contribute to strength, dimensional stability, and economy.
Q6. Which aggregate is generally classified as fine aggregate?
A. Gravel retained entirely on a 1-inch sieve
B. Sand passing the No. 4 sieve
, C. Crushed stone larger than 2 inches
D. Reinforcing steel
Answer: B. Sand passing the No. 4 sieve
Rationale: Fine aggregate generally consists of sand-sized particles that
predominantly pass the No. 4 sieve.
Q7. What does concrete slump primarily measure?
A. Compressive strength
B. Air content
C. Consistency and workability
D. Cement content
Answer: C. Consistency and workability
Rationale: The slump test provides an indication of the consistency and
relative workability of freshly mixed concrete.
Q8. What should be done if concrete has excessive slump because too
much water was added at the jobsite?
A. Add more water
B. Ignore the condition
C. Follow the approved mix-control procedure rather than arbitrarily adding
Exam Practice Questions And Correct
Answers (Verified Answers) Plus
Rationales 2027 Q&A | Instant
Download Pdf
Q1. What is the primary purpose of properly proportioning a concrete
mix?
A. To eliminate the need for curing
B. To increase the amount of water in the mixture
C. To achieve the required strength, durability, workability, and economy
D. To prevent all shrinkage
Answer: C. To achieve the required strength, durability, workability, and
economy
Rationale: Proper mix proportioning balances cementitious materials,
water, aggregates, and admixtures to produce concrete with the required
performance characteristics.
,Q2. Which material primarily binds the aggregate particles together in
conventional concrete?
A. Fine aggregate
B. Cement paste
C. Coarse aggregate
D. Mixing water
Answer: B. Cement paste
Rationale: Cement paste, consisting primarily of cement and water,
hydrates and binds the aggregate particles into a hardened mass.
Q3. What is the water-cement ratio?
A. The ratio of aggregate to cement
B. The ratio of water weight to cementitious-material weight
C. The ratio of cement volume to aggregate volume
D. The ratio of fine aggregate to coarse aggregate
Answer: B. The ratio of water weight to cementitious-material weight
Rationale: The water-cement ratio is a major factor affecting concrete
strength, permeability, and durability.
Q4. Increasing the water-cement ratio generally has what effect on
hardened concrete?
,A. Increases strength
B. Decreases permeability
C. Decreases strength
D. Eliminates shrinkage
Answer: C. Decreases strength
Rationale: Excess mixing water creates additional capillary pores after
evaporation, generally reducing strength and increasing permeability.
Q5. What is the main purpose of aggregate in concrete?
A. To provide bulk and structural stability
B. To replace all cement
C. To eliminate curing
D. To increase water demand intentionally
Answer: A. To provide bulk and structural stability
Rationale: Aggregates make up most of the concrete volume and
contribute to strength, dimensional stability, and economy.
Q6. Which aggregate is generally classified as fine aggregate?
A. Gravel retained entirely on a 1-inch sieve
B. Sand passing the No. 4 sieve
, C. Crushed stone larger than 2 inches
D. Reinforcing steel
Answer: B. Sand passing the No. 4 sieve
Rationale: Fine aggregate generally consists of sand-sized particles that
predominantly pass the No. 4 sieve.
Q7. What does concrete slump primarily measure?
A. Compressive strength
B. Air content
C. Consistency and workability
D. Cement content
Answer: C. Consistency and workability
Rationale: The slump test provides an indication of the consistency and
relative workability of freshly mixed concrete.
Q8. What should be done if concrete has excessive slump because too
much water was added at the jobsite?
A. Add more water
B. Ignore the condition
C. Follow the approved mix-control procedure rather than arbitrarily adding
