← All ACI Flashcard Decks

Decorative Concrete & Stamping Flashcards

7 cards from real ACI practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 7 Decorative Concrete & Stamping flashcards as text
  1. What is the purpose of back-rolling a sealer coat applied to stamped concrete?

    Answer: To remove excess sealer and prevent puddle buildup in low areas

    Back-rolling after spraying or rolling distributes sealer evenly and prevents it from pooling in the stamped texture depressions, which can cause whitening or peeling.

  2. Acid staining relies on which chemical reaction to produce color in concrete?

    Answer: Reaction between acid and free lime (calcium hydroxide) in hardened concrete

    Acid stains react with calcium hydroxide in cured concrete to form colored metallic salts that permanently bond with the concrete surface.

  3. Which of the following best describes 'integral color' in decorative concrete?

    Answer: Color mixed throughout the entire concrete batch before placement

    Integral color is a pigment added to the concrete mix so that color is uniform throughout the full depth of the slab, not just on the surface.

  4. What is the function of a texture mat (skin) in decorative stamping?

    Answer: To impart a surface texture without creating a repeating joint pattern

    Seamless texture skins or mats apply realistic surface texture — such as stone or slate grain — without the visible repeat lines that ridged stamp tools produce.

  5. Why is it important to keep stamp tool patterns aligned during a decorative pour?

    Answer: Misalignment creates visible breaks in the pattern that look unnatural

    Misaligned stamp tools disrupt the repeating decorative pattern, making joints and grout lines appear crooked or inconsistent, which compromises the appearance.

  6. What minimum concrete compressive strength is typically required before applying a chemical stain to a new slab?

    Answer: 2,500 psi or full cure (28 days recommended)

    Staining should be done after the concrete reaches adequate strength and cure — typically after 28 days — to ensure the stain reacts properly and color is consistent.

  7. Which condition most commonly causes stamp tool impressions to lose detail and appear shallow?

    Answer: Concrete that is too stiff (over-set) at the time of stamping

    When concrete has stiffened beyond the workable stamping window, stamp tools cannot penetrate deeply enough to transfer full pattern detail.