ACI Concrete Strength Testing Technician Certification
Practice Examination Newest 2025–2026 Edition |
Complete Test Bank with 200 Most Tested Questions
and 100% Verified Answers with Detailed Rationales |
Comprehensive Review Based on Current ACI Concrete
Strength Testing Technician Certification Requirements |
Tutor Verified Success | Grade A+ | Instant Download
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1. What is the primary purpose of ASTM C31 in concrete testing?
A. Determining concrete density
B. Making and curing concrete test specimens
C. Measuring air content
D. Testing cement composition
Correct Answer: B ✓ (Making and curing concrete test specimens)
_Rationale: ASTM C31 governs the procedures for preparing and curing concrete
test cylinders and beams under field conditions to ensure reliable strength
results._
2. According to ASTM C143, what property does the slump test measure?
A. Compressive strength
B. Workability of fresh concrete
C. Air content
D. Density of hardened concrete
,Correct Answer: B ✓ (Workability of fresh concrete)
_Rationale: The slump test evaluates the consistency and workability of freshly
mixed concrete._
3. What is the standard size of a concrete compression test cylinder in the
United States?
A. 100 mm × 200 mm
B. 150 mm × 300 mm
C. 200 mm × 400 mm
D. 75 mm × 150 mm
Correct Answer: B ✓ (150 mm × 300 mm)
_Rationale: The standard cylinder size used for compressive strength testing is 6 ×
12 inches (150 × 300 mm)._
4. Which tool is used to consolidate concrete in cylinder molds?
A. Tamping rod
B. Rebound hammer
C. Vibrating scale
D. Air meter
Correct Answer: A ✓ (Tamping rod)
_Rationale: A tamping rod is used to rod and consolidate fresh concrete layers in
molds._
5. What is the main purpose of curing concrete specimens?
A. Increase workability
B. Maintain moisture and temperature for hydration
C. Reduce cement content
D. Speed up drying
,Correct Answer: B ✓ (Maintain moisture and temperature for hydration)
_Rationale: Proper curing ensures hydration continues, leading to accurate
strength development._
6. ASTM C39 is used to determine which property?
A. Slump
B. Air content
C. Compressive strength of hardened concrete
D. Temperature of concrete
Correct Answer: C ✓ (Compressive strength of hardened concrete)
_Rationale: ASTM C39 specifies the procedure for compressive strength testing of
cylindrical concrete specimens._
7. When should slump tests be performed?
A. After concrete hardens
B. Before mixing cement
C. Immediately after sampling fresh concrete
D. Only in laboratory conditions
Correct Answer: C ✓ (Immediately after sampling fresh concrete)
_Rationale: Slump must be tested on fresh concrete before initial setting occurs._
8. What is the minimum number of layers used when casting a cylinder?
A. 1
B. 2
C. 3
D. 4
, Correct Answer: C ✓ (3)
_Rationale: Cylinders are typically filled in three equal layers for proper
consolidation._
9. How many roddings are required per layer for a 6×12 cylinder?
A. 10
B. 15
C. 25
D. 50
Correct Answer: C ✓ (25)
_Rationale: ASTM standards require 25 strokes per layer for standard cylinders._
10.What is the acceptable range of slump for normal structural concrete
(typical field use)?
A. 0–1 in
B. 1–6 in
C. 6–10 in
D. 10–15 in
Correct Answer: B ✓ (1–6 in)
_Rationale: Most structural concrete specifications fall within 1–6 inches of slump
depending on design._
11.What is the purpose of rodding concrete in a mold?
A. Remove cement
B. Increase air content
C. Eliminate voids and ensure compaction
D. Dry the concrete
Practice Examination Newest 2025–2026 Edition |
Complete Test Bank with 200 Most Tested Questions
and 100% Verified Answers with Detailed Rationales |
Comprehensive Review Based on Current ACI Concrete
Strength Testing Technician Certification Requirements |
Tutor Verified Success | Grade A+ | Instant Download
1. What is the primary purpose of ASTM C31 in concrete testing?
A. Determining concrete density
B. Making and curing concrete test specimens
C. Measuring air content
D. Testing cement composition
Correct Answer: B ✓ (Making and curing concrete test specimens)
_Rationale: ASTM C31 governs the procedures for preparing and curing concrete
test cylinders and beams under field conditions to ensure reliable strength
results._
2. According to ASTM C143, what property does the slump test measure?
A. Compressive strength
B. Workability of fresh concrete
C. Air content
D. Density of hardened concrete
,Correct Answer: B ✓ (Workability of fresh concrete)
_Rationale: The slump test evaluates the consistency and workability of freshly
mixed concrete._
3. What is the standard size of a concrete compression test cylinder in the
United States?
A. 100 mm × 200 mm
B. 150 mm × 300 mm
C. 200 mm × 400 mm
D. 75 mm × 150 mm
Correct Answer: B ✓ (150 mm × 300 mm)
_Rationale: The standard cylinder size used for compressive strength testing is 6 ×
12 inches (150 × 300 mm)._
4. Which tool is used to consolidate concrete in cylinder molds?
A. Tamping rod
B. Rebound hammer
C. Vibrating scale
D. Air meter
Correct Answer: A ✓ (Tamping rod)
_Rationale: A tamping rod is used to rod and consolidate fresh concrete layers in
molds._
5. What is the main purpose of curing concrete specimens?
A. Increase workability
B. Maintain moisture and temperature for hydration
C. Reduce cement content
D. Speed up drying
,Correct Answer: B ✓ (Maintain moisture and temperature for hydration)
_Rationale: Proper curing ensures hydration continues, leading to accurate
strength development._
6. ASTM C39 is used to determine which property?
A. Slump
B. Air content
C. Compressive strength of hardened concrete
D. Temperature of concrete
Correct Answer: C ✓ (Compressive strength of hardened concrete)
_Rationale: ASTM C39 specifies the procedure for compressive strength testing of
cylindrical concrete specimens._
7. When should slump tests be performed?
A. After concrete hardens
B. Before mixing cement
C. Immediately after sampling fresh concrete
D. Only in laboratory conditions
Correct Answer: C ✓ (Immediately after sampling fresh concrete)
_Rationale: Slump must be tested on fresh concrete before initial setting occurs._
8. What is the minimum number of layers used when casting a cylinder?
A. 1
B. 2
C. 3
D. 4
, Correct Answer: C ✓ (3)
_Rationale: Cylinders are typically filled in three equal layers for proper
consolidation._
9. How many roddings are required per layer for a 6×12 cylinder?
A. 10
B. 15
C. 25
D. 50
Correct Answer: C ✓ (25)
_Rationale: ASTM standards require 25 strokes per layer for standard cylinders._
10.What is the acceptable range of slump for normal structural concrete
(typical field use)?
A. 0–1 in
B. 1–6 in
C. 6–10 in
D. 10–15 in
Correct Answer: B ✓ (1–6 in)
_Rationale: Most structural concrete specifications fall within 1–6 inches of slump
depending on design._
11.What is the purpose of rodding concrete in a mold?
A. Remove cement
B. Increase air content
C. Eliminate voids and ensure compaction
D. Dry the concrete
