CONCRETE TEST FINAL TEST 2026
QUESTIONS WITH CORRECT ANSWERS
GRADED A+
◍ How many layers of equal volume must the concrete be placed in when
filling the measuring bowl of the air meter?.
Answer: Two.
◍ Dimensions of tamping rod.
Answer: 5/8" diameterBoth ends roundedLength is 4-24" of the overall cone
height
◍ Why is collecting a representative sample of concrete important?.
Answer: It is as important as executing the test methods to obtain reliable
results.
◍ When is wet screening necessary?.
Answer: When the mixture contains aggregate with a nominal maximum
size greater than 1 in. (25 mm).
◍ What conditions must be met for an initial meter reading to be valid?.
Answer: The meter must not be leaking, the liquid level must stabilize
within 6 min, and the foam on the surface of the liquid must not be greater
than 2 full percent divisions.
◍ According to Test Method C138/C138M, what is the air content (in percent)
of the following concrete batch?The theoretical density computed on an
air-free basis is 168 lb/cu ft.The density is 158 lb/cu ft..
Answer: 6.0% = [(168 - 158)/168] x 100
◍ How far should the tamping rod penetrate into the underlying layer when
rodding each upper layer of concrete in a cylinder?.
, Answer: About 1 in. (25 mm).
◍ Strike off plate dimensions.
Answer: 1/4" thick of metal1/2" thick if glass/acrylicLength/Width exceed
2" around device
◍ What types of equipment are covered for sampling concrete?.
Answer: Stationary mixers, paving mixers, revolving drum truck mixers,
and continuous mixers.
◍ Rod versus Vibrate on Air Pressure.
Answer: Greater than 3" slump = Rod1-3" = eitherLess than 1" = Vibrate
◍ Cylinder seive.
Answer: Wet seive aggregate through 2"
◍ What is the initial curing temperature range for concrete mixtures with
specified strengths of 6000 psi [40 MPa] or greater?.
Answer: 68 and 78°F (20 and 26°C).
◍ Internal vibrator frequency should be atleast.
Answer: 9000 vibrations per minute (150 Hz)
◍ Measuring bowl of pressure test capacity of atleast.
Answer: 0.2 ft3
◍ T/F When concrete contains large aggregate, the testing technician should
wet-sieve the sample before making density (unit weight) tests for use in
yield computations..
Answer: False
◍ Mallet mass.
Answer: 1.25 +/- 0.5 lb
◍ Type of aggregate for Volumetric.
Answer: Any type
◍ T/F After strike off of the measure used to determine density, a small
quantity of concrete may be added to correct a deficiency..
QUESTIONS WITH CORRECT ANSWERS
GRADED A+
◍ How many layers of equal volume must the concrete be placed in when
filling the measuring bowl of the air meter?.
Answer: Two.
◍ Dimensions of tamping rod.
Answer: 5/8" diameterBoth ends roundedLength is 4-24" of the overall cone
height
◍ Why is collecting a representative sample of concrete important?.
Answer: It is as important as executing the test methods to obtain reliable
results.
◍ When is wet screening necessary?.
Answer: When the mixture contains aggregate with a nominal maximum
size greater than 1 in. (25 mm).
◍ What conditions must be met for an initial meter reading to be valid?.
Answer: The meter must not be leaking, the liquid level must stabilize
within 6 min, and the foam on the surface of the liquid must not be greater
than 2 full percent divisions.
◍ According to Test Method C138/C138M, what is the air content (in percent)
of the following concrete batch?The theoretical density computed on an
air-free basis is 168 lb/cu ft.The density is 158 lb/cu ft..
Answer: 6.0% = [(168 - 158)/168] x 100
◍ How far should the tamping rod penetrate into the underlying layer when
rodding each upper layer of concrete in a cylinder?.
, Answer: About 1 in. (25 mm).
◍ Strike off plate dimensions.
Answer: 1/4" thick of metal1/2" thick if glass/acrylicLength/Width exceed
2" around device
◍ What types of equipment are covered for sampling concrete?.
Answer: Stationary mixers, paving mixers, revolving drum truck mixers,
and continuous mixers.
◍ Rod versus Vibrate on Air Pressure.
Answer: Greater than 3" slump = Rod1-3" = eitherLess than 1" = Vibrate
◍ Cylinder seive.
Answer: Wet seive aggregate through 2"
◍ What is the initial curing temperature range for concrete mixtures with
specified strengths of 6000 psi [40 MPa] or greater?.
Answer: 68 and 78°F (20 and 26°C).
◍ Internal vibrator frequency should be atleast.
Answer: 9000 vibrations per minute (150 Hz)
◍ Measuring bowl of pressure test capacity of atleast.
Answer: 0.2 ft3
◍ T/F When concrete contains large aggregate, the testing technician should
wet-sieve the sample before making density (unit weight) tests for use in
yield computations..
Answer: False
◍ Mallet mass.
Answer: 1.25 +/- 0.5 lb
◍ Type of aggregate for Volumetric.
Answer: Any type
◍ T/F After strike off of the measure used to determine density, a small
quantity of concrete may be added to correct a deficiency..
