ACI Concrete Field Testing Technician
Grade I Practice Exam Questions And
Correct Answers (Verified Answers) Plus
Rationales 2026 Q&A Instant Download
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1. What is the primary purpose of slump testing fresh concrete?
A) Measure compressive strength
B) Determine workability and consistency
C) Measure air content
D) Determine cement content
Answer: Determine workability and consistency
Rationale: Slump testing evaluates the consistency and workability of fresh
concrete, not strength or composition.
2. Which ASTM standard governs slump testing?
A) ASTM C1064
B) ASTM C143
C) ASTM C138
D) ASTM C231
Answer: ASTM C143
Rationale: ASTM C143 specifies the procedure for slump testing of
hydraulic-cement concrete.
,3. What tool is used to measure concrete temperature?
A) Thermometer
B) Hydrometer
C) Pycnometer
D) Rebound hammer
Answer: Thermometer
Rationale: A calibrated concrete thermometer is used per ASTM C1064.
4. What is the required compaction method for slump test specimens?
A) Shaking
B) Tamping rod in layers
C) Vibrating table only
D) Free fall placement
Answer: Tamping rod in layers
Rationale: Concrete is placed in three layers and rodded 25 times per layer.
5. Which test measures air content using pressure method?
A) ASTM C173
B) ASTM C231
C) ASTM C138
D) ASTM C143
Answer: ASTM C231
Rationale: The pressure method is used for normal-density concrete air
content.
6. What is the purpose of ASTM C172?
A) Slump testing
B) Sampling fresh concrete
C) Air testing
, D) Strength testing
Answer: Sampling fresh concrete
Rationale: ASTM C172 governs how to obtain representative samples.
7. What is the standard mold size for compressive strength cylinders?
A) 4x8 in or 6x12 in
B) 3x6 in only
C) 5x10 in only
D) 2x4 in
Answer: 4x8 in or 6x12 in
Rationale: These are standard cylinder sizes per ASTM C31.
8. How soon must concrete cylinders be moved after casting?
A) 6 hours
B) 24 hours
C) 48 hours
D) 72 hours
Answer: 48 hours
Rationale: Cylinders must remain undisturbed for 24–48 hours before
transport.
9. What is the purpose of rodding in sampling fresh concrete?
A) Increase air content
B) Consolidate concrete
C) Reduce cement content
D) Measure slump
Answer: Consolidate concrete
Rationale: Rodding removes voids and ensures uniform density.
Grade I Practice Exam Questions And
Correct Answers (Verified Answers) Plus
Rationales 2026 Q&A Instant Download
1. What is the primary purpose of slump testing fresh concrete?
A) Measure compressive strength
B) Determine workability and consistency
C) Measure air content
D) Determine cement content
Answer: Determine workability and consistency
Rationale: Slump testing evaluates the consistency and workability of fresh
concrete, not strength or composition.
2. Which ASTM standard governs slump testing?
A) ASTM C1064
B) ASTM C143
C) ASTM C138
D) ASTM C231
Answer: ASTM C143
Rationale: ASTM C143 specifies the procedure for slump testing of
hydraulic-cement concrete.
,3. What tool is used to measure concrete temperature?
A) Thermometer
B) Hydrometer
C) Pycnometer
D) Rebound hammer
Answer: Thermometer
Rationale: A calibrated concrete thermometer is used per ASTM C1064.
4. What is the required compaction method for slump test specimens?
A) Shaking
B) Tamping rod in layers
C) Vibrating table only
D) Free fall placement
Answer: Tamping rod in layers
Rationale: Concrete is placed in three layers and rodded 25 times per layer.
5. Which test measures air content using pressure method?
A) ASTM C173
B) ASTM C231
C) ASTM C138
D) ASTM C143
Answer: ASTM C231
Rationale: The pressure method is used for normal-density concrete air
content.
6. What is the purpose of ASTM C172?
A) Slump testing
B) Sampling fresh concrete
C) Air testing
, D) Strength testing
Answer: Sampling fresh concrete
Rationale: ASTM C172 governs how to obtain representative samples.
7. What is the standard mold size for compressive strength cylinders?
A) 4x8 in or 6x12 in
B) 3x6 in only
C) 5x10 in only
D) 2x4 in
Answer: 4x8 in or 6x12 in
Rationale: These are standard cylinder sizes per ASTM C31.
8. How soon must concrete cylinders be moved after casting?
A) 6 hours
B) 24 hours
C) 48 hours
D) 72 hours
Answer: 48 hours
Rationale: Cylinders must remain undisturbed for 24–48 hours before
transport.
9. What is the purpose of rodding in sampling fresh concrete?
A) Increase air content
B) Consolidate concrete
C) Reduce cement content
D) Measure slump
Answer: Consolidate concrete
Rationale: Rodding removes voids and ensures uniform density.
