1. How many samples are necessary when examining a construction defect?

    1. 1

    2. 3

    3. Every project is different and should be approached on a case by case basis.

  2. For a suspected low-strength issue, cores must break equal to test cylinders to be acceptable.

    1. True

    2. False

  3. A petrographic examination can provide which of the items below?

    1. Detection of a deleterious concrete reaction not always observable when examining the overall structure.

    2. Estimated range of percentage of concrete air content.

    3. Depth of carbonation of the concrete.

  4. Air void parameters are best determined by which test?

    1. ASTM C 856

    2. ASTM C 457

  5. Concrete tested for compressive strength using a rebound hammer should be used to accept or reject concrete.

    1. True

    2. False

Answers: 1-C, 2-B (average of 3 cores must be 85% of specified strength), 3-A, B and C, 4-B, 5-B

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