Free NCCER Concrete Finisher Assessment Practice Questions

Sample Practice Questions

Try these 10 sample questions from the NCCER Concrete Finisher Assessment practice bank. Each includes the answer and explanation. Continue with the interactive practice above to review the full question set.

1. 1A finisher is explaining what holds the sand and stone together in a hardened concrete slab. Which component performs that binding role?

   1. A.Cement and water pasteCorrect answer: A
   2. B.Fine and coarse aggregate
   3. C.Discrete reinforcing fibers
   4. D.Entrained air void system

   Explanation: The American Cement Association states, "As the cement reacts chemically with the water, it binds the aggregates into a rock-like mass." The binder in the slab is therefore the cement and water paste.

   Reference: Cement & Concrete FAQ — Cement and Concrete 101, difference between cement and concrete

2. 2Before placing a slab on grade, which subgrade condition should a finisher flag for removal and replacement before compaction?

   1. A.Compacted granular fill
   2. B.A soft spot beneath the slabCorrect answer: B
   3. C.Uniformly compacted soil
   4. D.Fine-graded aggregate base

   Explanation: NRMCA states, "All topsoil and soft spots should be removed." The other described materials are legitimate slab support when properly compacted.

   Reference: CIP 4: Cracking Concrete Surfaces — p. 1, HOW to Prevent or Minimize Cracking?, Subgrade and Formwork

3. 3A slab-on-grade will receive moisture-sensitive vinyl flooring. Which under-slab layer is specifically intended to limit upward water-vapor transmission?

   1. A.Compacted granular base
   2. B.Plastic vapor retarderCorrect answer: B
   3. C.Fine grading layer
   4. D.Capillary drainage layer

   Explanation: ACI states, "A vapor retarder is a material that is intended to minimize the transmission of moisture upward through the slab from sources below." A vinyl floor is moisture-sensitive, so the vapor retarder is the specified moisture-control layer.

   Reference: ACI 302.1R-04: Guide for Concrete Floor and Slab Construction — Section 3.2.3, Moisture protection

4. 4A walkway has a specified drainage cross slope. Which elevation reference should the tops of its edge forms follow?

   1. A.Specified finished-surface gradeCorrect answer: A
   2. B.Existing subgrade elevation
   3. C.Adjacent footing elevation
   4. D.Nearby curb elevation

   Explanation: The cement association states, "Where slope for drainage is indicated on plans, forms shall be sloped to obtain desired finish grade." The plan's finished-surface grade controls the edge-form setup.

   Reference: Finishing Concrete Slabs with Color and Texture — Appendix, Forms, drainage slope

5. 5Fresh concrete has been placed for an interior slab and its top is above the planned grade. Which operation removes the excess and establishes grade?

   1. A.Screeding or strikeoffCorrect answer: A
   2. B.Floating or bull floating
   3. C.Steel troweling
   4. D.Curing compound application

   Explanation: The cement association defines the operation: "Screeding or strikeoff is the process of cutting off excess concrete to bring the top surface of the slab to proper grade." The slab first needs strikeoff.

   Reference: Working with Concrete — Placing and Finishing Concrete, Screeding

6. 6A crew casts full-size wall panels horizontally on a ground-supported slab, then lifts them into their final vertical positions. Which construction method is this?

   1. A.Tilt-up constructionCorrect answer: A
   2. B.Cast-in-place wall forming
   3. C.Precast plant panel construction
   4. D.Vertical slipform construction

   Explanation: The Tilt-Up Concrete Association explains, "concrete wall panels are typically cast in a horizontal position on a ground-supported slab." This describes the site-cast lift sequence of tilt-up construction.

   Reference: Wall Bracing to Slab-on-Ground Floors — Introduction, tilt-up construction method

7. 7After cleaning a stable horizontal crack for a gravity-fed resin seal, what minimum drying period does ACI RAP-2 specify before resin application?

   1. A.6 hours
   2. B.12 hours
   3. C.24 hoursCorrect answer: C
   4. D.48 hours

   Explanation: ACI RAP-2 states, "Allow the repair area to dry for at least 24 hours before applying the resin." The minimum specified drying period is 24 hours; a longer period is not the minimum.

   Reference: Crack Repair by Gravity Feed with Resin (ACI RAP-2) — p. 4, How do I prepare the surface?

8. 8A crew receives plastic concrete batched at a central plant and delivered to the site for placement. What type of concrete supply is this?

   1. A.Site-mixed concrete
   2. B.Ready mixed concreteCorrect answer: B
   3. C.Precast concrete
   4. D.Roller-compacted concrete

   Explanation: The association defines the category directly: "Ready mixed refers to concrete that is batched for delivery from a central plant instead of being mixed on the jobsite." The delivered batch matches that definition.

   Reference: Applications of Cement — Types of Concrete, Ready Mixed Concrete

9. 9A slab-on-grade crew checks the ground immediately before placement in winter. Which condition requires the crew to withhold concrete placement?

   1. A.Dampened compacted soil
   2. B.Sloped granular fill
   3. C.A frozen subgradeCorrect answer: C
   4. D.A compacted soil base

   Explanation: NRMCA instructs, "do not place concrete on a frozen subgrade." The frozen condition, rather than the listed usable support preparations, prevents placement.

   Reference: CIP 4: Cracking Concrete Surfaces — p. 1, HOW to Prevent or Minimize Cracking?, Subgrade and Formwork

10. 10Before a slab-on-ground pour, the crew wants the field check that ACI says is generally more indicative of whether the soil support will withstand loading. Which check is it?

    1. A.Proofrolling of the soil-support systemCorrect answer: A
    2. B.In-place soil moisture-content testing
    3. C.In-place soil density testing
    4. D.Gradation testing of granular fill

    Explanation: ACI states, "In most cases, proofrolling results are far more indicative of the ability of the soil-support system to withstand loading than the results from in-place tests of moisture content or density are." Proofrolling is the comparative field check.

    Reference: ACI 302.1R-04: Guide for Concrete Floor and Slab Construction — Section 3.2.2, Soil-support system