ACI Concrete Laboratory Testing Technician Level I
Certification Practice Examination Newest 2025–
2026 Edition | Complete Mega Test Bank with 200
Most Tested Questions and 100% Verified Answers
with Detailed Rationales | Comprehensive Review
Based on Current ACI Concrete Laboratory Testing
Technician Level I Certification Requirements |
Tutor Verified Success | Grade A+ | Instant
Download PDF
1. A concrete sample for laboratory testing should be obtained in accordance
with which ASTM standard?
A. ASTM C31
B. ASTM C172
C. ASTM C39
D. ASTM C94
Answer: B ✓ [B. ASTM C172]
Rationale: ASTM C172 specifies the standard practice for sampling freshly mixed
concrete, ensuring representative samples are obtained for testing.
2. What is the primary purpose of performing a slump test?
A. Measure compressive strength
B. Determine air content
C. Assess workability and consistency
D. Measure cement content
,Answer: C ✓ [C. Assess workability and consistency]
Rationale: The slump test (ASTM C143) evaluates the consistency and
workability of fresh concrete.
3. Which tool is used to measure concrete slump?
A. Proctor mold
B. Abrams cone
C. Vicat apparatus
D. Flow table
Answer: B ✓ [B. Abrams cone]
Rationale: The Abrams cone (slump cone) is used in ASTM C143 to measure
concrete slump.
4. The standard size of a slump cone is:
A. 6 in × 12 in
B. 8 in × 12 in
C. 4 in × 8 in
D. 10 in × 20 in
Answer: A ✓ [A. 6 in × 12 in]
Rationale: The slump cone is 12 inches high with 8-inch base and 4-inch top
diameter.
5. Concrete cylinders for compressive strength testing are most commonly:
A. 3 in × 6 in
B. 6 in × 12 in
C. 4 in × 8 in only
D. 8 in × 16 in
Answer: B ✓ [B. 6 in × 12 in]
Rationale: 6×12 inch cylinders are standard per ASTM C31 and C39 for strength
testing.
6. Which ASTM standard covers making and curing concrete test specimens in
the field?
, A. C31
B. C39
C. C143
D. C150
Answer: A ✓ [A. ASTM C31]
Rationale: ASTM C31 governs the preparation and curing of concrete test
specimens in the field.
7. The purpose of rodding concrete in a mold is to:
A. Remove excess water
B. Compact the concrete
C. Increase cement hydration
D. Measure density
Answer: B ✓ [B. Compact the concrete]
Rationale: Rodding removes voids and ensures proper compaction of concrete
specimens.
8. Compressive strength of concrete is determined using:
A. ASTM C31
B. ASTM C39
C. ASTM C143
D. ASTM C138
Answer: B ✓ [B. ASTM C39]
Rationale: ASTM C39 specifies the test method for compressive strength of
cylindrical concrete specimens.
9. The unit of compressive strength is typically:
A. psi
B. kN/m³
C. lb/ft³
D. kg/m²
, Answer: A ✓ [A. psi]
Rationale: Concrete compressive strength is commonly expressed in pounds per
square inch (psi).
10.Air content in concrete is commonly measured using:
A. Flow table
B. Pressure method
C. Slump cone
D. Vicat needle
Answer: B ✓ [B. Pressure method]
Rationale: ASTM C231 uses the pressure method to determine air content in
fresh concrete.
11.The main purpose of air in concrete is to:
A. Increase weight
B. Improve freeze-thaw durability
C. Reduce cement content
D. Increase slump only
Answer: B ✓ [B. Improve freeze-thaw durability]
Rationale: Entrained air improves resistance to freeze-thaw cycles in concrete.
12.Unit weight of concrete is determined by:
A. ASTM C138
B. ASTM C39
C. ASTM C31
D. ASTM C1064
Answer: A ✓ [A. ASTM C138]
Rationale: ASTM C138 measures the density (unit weight) of fresh concrete.
13.The term “yield” in concrete refers to:
A. Strength gain
B. Volume produced per batch
Certification Practice Examination Newest 2025–
2026 Edition | Complete Mega Test Bank with 200
Most Tested Questions and 100% Verified Answers
with Detailed Rationales | Comprehensive Review
Based on Current ACI Concrete Laboratory Testing
Technician Level I Certification Requirements |
Tutor Verified Success | Grade A+ | Instant
Download PDF
1. A concrete sample for laboratory testing should be obtained in accordance
with which ASTM standard?
A. ASTM C31
B. ASTM C172
C. ASTM C39
D. ASTM C94
Answer: B ✓ [B. ASTM C172]
Rationale: ASTM C172 specifies the standard practice for sampling freshly mixed
concrete, ensuring representative samples are obtained for testing.
2. What is the primary purpose of performing a slump test?
A. Measure compressive strength
B. Determine air content
C. Assess workability and consistency
D. Measure cement content
,Answer: C ✓ [C. Assess workability and consistency]
Rationale: The slump test (ASTM C143) evaluates the consistency and
workability of fresh concrete.
3. Which tool is used to measure concrete slump?
A. Proctor mold
B. Abrams cone
C. Vicat apparatus
D. Flow table
Answer: B ✓ [B. Abrams cone]
Rationale: The Abrams cone (slump cone) is used in ASTM C143 to measure
concrete slump.
4. The standard size of a slump cone is:
A. 6 in × 12 in
B. 8 in × 12 in
C. 4 in × 8 in
D. 10 in × 20 in
Answer: A ✓ [A. 6 in × 12 in]
Rationale: The slump cone is 12 inches high with 8-inch base and 4-inch top
diameter.
5. Concrete cylinders for compressive strength testing are most commonly:
A. 3 in × 6 in
B. 6 in × 12 in
C. 4 in × 8 in only
D. 8 in × 16 in
Answer: B ✓ [B. 6 in × 12 in]
Rationale: 6×12 inch cylinders are standard per ASTM C31 and C39 for strength
testing.
6. Which ASTM standard covers making and curing concrete test specimens in
the field?
, A. C31
B. C39
C. C143
D. C150
Answer: A ✓ [A. ASTM C31]
Rationale: ASTM C31 governs the preparation and curing of concrete test
specimens in the field.
7. The purpose of rodding concrete in a mold is to:
A. Remove excess water
B. Compact the concrete
C. Increase cement hydration
D. Measure density
Answer: B ✓ [B. Compact the concrete]
Rationale: Rodding removes voids and ensures proper compaction of concrete
specimens.
8. Compressive strength of concrete is determined using:
A. ASTM C31
B. ASTM C39
C. ASTM C143
D. ASTM C138
Answer: B ✓ [B. ASTM C39]
Rationale: ASTM C39 specifies the test method for compressive strength of
cylindrical concrete specimens.
9. The unit of compressive strength is typically:
A. psi
B. kN/m³
C. lb/ft³
D. kg/m²
, Answer: A ✓ [A. psi]
Rationale: Concrete compressive strength is commonly expressed in pounds per
square inch (psi).
10.Air content in concrete is commonly measured using:
A. Flow table
B. Pressure method
C. Slump cone
D. Vicat needle
Answer: B ✓ [B. Pressure method]
Rationale: ASTM C231 uses the pressure method to determine air content in
fresh concrete.
11.The main purpose of air in concrete is to:
A. Increase weight
B. Improve freeze-thaw durability
C. Reduce cement content
D. Increase slump only
Answer: B ✓ [B. Improve freeze-thaw durability]
Rationale: Entrained air improves resistance to freeze-thaw cycles in concrete.
12.Unit weight of concrete is determined by:
A. ASTM C138
B. ASTM C39
C. ASTM C31
D. ASTM C1064
Answer: A ✓ [A. ASTM C138]
Rationale: ASTM C138 measures the density (unit weight) of fresh concrete.
13.The term “yield” in concrete refers to:
A. Strength gain
B. Volume produced per batch
