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ACI WRITTEN EXAM QUE STIONS
WITH CORRECT ANSWERS
Question : The method of determining air content of concrete
containing lightweight aggregate is the pressure method
Correct answer: False. Relatively dense
Question : Is the following statement true or false? When
making a test cylinder from concrete being used in construction, the field technician must also measure the slump of the concrete.
Correct answer: True
Question : While the technician is checking the slump of the
concrete, there is a decided falling away or shearing off of concrete from one side of the sample. What should the technician do?
Correct answer: Disregard the test and retest on another
portion of the sample.
Question : Preparation of specimens for transport includes:
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Correct answer: Determination that at least 8 hours has
elapsed since final set.
Question : If the aggregate correction factor for a given source
of fine and coarse aggregate is found to be 0.2% in a pressure air meter, and an air content value of 5.0% is read on the gauge of the same air meter containing concrete with the same aggregate, what is the correct air content?
Correct answer: 4.8%
Question : Strength test specimens transported from the field
to the testing laboratory must be:
Correct answer: Protected from jarring, moisture loss, and
freezing
Question : Tests for slump and air content must be started
within ________ after obtaining the final portion of the composite sample.
Correct answer: 5 MInutes
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Question : The minimum size for samples to be used for
strength test is:
Correct answer: 1 cubic foot
Question : Is the following statement true or false? After
strike off of the measure used to determine density, a small quantity of concrete may be added to correct a deficiency.
Correct answer: False
Question : For normal strength concretes, what temperature
range must be maintained for test cylinders during initial curing?
Correct answer: 60 to 80 degrees f (16 to 27 degrees C)
Question : Is the following statement true or false? When
concrete contains large aggregate, the testing technician should wet-sieved the sample before making density (unit weight) tests for use in yield computations.
Correct answer: False
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Question : When determining the temperature of fresh mixed
concrete, what is the minimum amount of concrete cover in all directions around the sensor of the temperature measuring device?
Correct answer: 3 inches ( 75MM)
Question : Is the following statement true or false? The sides
of the slump mold should be lightly tapped to consolidate the concrete in the mold.
Correct answer: false
Question : Is the following statement true or false? Unless
specified otherwise, strength test specimens molded from concrete having a slump less than 25mm (1 inch) must be consolidated by vibration.
Correct answer: True
Question : Is the following statement true or false? Test
cylinders may be capped with a thin layer of portland cement paste which is permitted to harden and cure with the specimen