Exam Practice Questions And Correct

ACI Concrete Flatwork Finisher Certification Exam Practice Questions And Correct Answers (Verified Answers) Plus Rationales 2026 Q&A | Instant Download Pdf

• What is the primary purpose of finishing concrete?

a) To increase the weight of concrete

b) To ensure the concrete is waterproof

c) To produce a smooth, uniform surface

d) To reduce concrete strength

Rationale: Proper finishing ensures a smooth, uniform surface and

aids in durability and appearance.

• What is the ideal slump range for a typical flatwork slab?
• 8-10 inches
• 3-4 inches
• 0-1 inches
• 6-8 inches 1 / 4

Rationale: A 3-4 inch slump is generally workable for most flatwork

applications without excessive bleeding or segregation.

• Which tool is commonly used for initial screeding of concrete?

a) Straightedge (screed board)

b) Trowel

c) Float

d) Bull float

Rationale: A straightedge is used to strike off excess concrete and

establish the grade during screeding.

• What is the purpose of bull floating?

a) To compact concrete

b) To smooth and level the surface after screeding

c) To cure concrete

d) To remove formwork

Rationale: Bull floating helps embed aggregate and brings cream

(fine particles and paste) to the surface for finishing.

• When should hand troweling begin?

a) Immediately after pouring

b) Before screeding

c) After the surface water has evaporated but concrete is still plastic

d) After final set

Rationale: Hand troweling should start when concrete is firm enough

to support the trowel without tearing. 2 / 4

• What is the main function of a float?

a) To mix concrete

b) To remove surface imperfections and embed coarse aggregate

c) To compact concrete

d) To apply curing compounds

Rationale: Floating produces a uniform, slightly textured surface and

prepares concrete for final troweling.

• What is the effect of finishing concrete too early?

a) Increases strength

b) Improves color

c) Causes segregation and surface defects

d) Improves durability

Rationale: Early finishing can bring excess water and fines to the

surface, weakening the slab and causing defects.

• What is the typical depth for saw-cut contraction joints in a 4-inch

slab?

• 1 inch
• 2 inches
• 1/4 of the slab thickness (approximately 1 inch)
• 1/2 of the slab thickness

Rationale: Cutting 1/4 of the slab thickness helps control cracking

due to shrinkage. 3 / 4

• What is the main purpose of concrete curing?

a) To dry the surface

b) To maintain adequate moisture and temperature for proper

hydration

c) To harden the concrete immediately

d) To make the concrete smooth

Rationale: Curing ensures hydration continues, which is essential for

strength and durability.

• Which of the following is NOT a common finishing defect?

a) Scaling

b) Dusting

c) Aggregate segregation during batching

d) Cracking

Rationale: Aggregate segregation during batching is a mixing issue,

not a finishing defect.

• How can bleeding be minimized in flatwork?

a) Increase slump

b) Add more water

c) Use proper mix design with well-graded aggregates

d) Delay finishing

Rationale: Proper mix design reduces bleeding by optimizing water-

cement ratio and aggregate gradation.

• / 4