ACI TEST QUESTIONS & ANSWERS
The total time allowed between obtaining the first and final portions of a composite
sample is - Answers - 15 minutes
When it is necessary to wet sieve the concrete sample, wet sieving should be
performed after the individual samples are remixed into a composite sample (T or F) -
Answers - F
Tests for slump, temperature, and air content must begin within ______ minutes after
obtaining the composite sample - Answers - 5 minutes
Begin molding test specimens within ______ minutes after obtaining the composite
sample - Answers - 15 minutes
The concrete samples should be protected from - Answers - the sun, wind, and other
sources of rapid evaporation, from contamination
When test specimens are to be molded, the minimum size of sample obtained is -
Answers - 28 L (1 ft^3)
The primary objective of the sampling process is to obtain a representative sample (T or
F) - Answers - T
When sampling from a revolving drum truck mixer collect concrete from ______ portions
of the batch - Answers - 2 or more
Submerge the sensing portion of the thermometer at least ______ inches into the
concrete - Answers - 3
Gently press concrete around the thermometer such that the_______ does not
affect the reading. - Answers - ambient air temp
The thermometer must remain in the concrete during the measurement for a minimum
of ______ minutes. In addition, the temperature measurement must be completed within
_______ minutes after obtaining the sample. - Answers - 2, 5
The temperature of freshly mixed concrete is measured and recorded to the nearest
_____ - Answers - 1 degree
SLUMP TEST - Answers -
****The slump test does not provide an indication of the water content of a concrete
mixture. - Answers - F
, A slump mold can be fabricated from both plastic and metal. - Answers - T
****The length of the tamping for the slump test shall be approximately - Answers -
The slump test is applicable to concrete having a coarse aggregate up to _______ inch
in size. - Answers - 1.5 inches
The height of the slump cone is - Answers - 12 in
6. The exterior of the slump cone is tapped 10 to 15 times after rodding each layer. -
Answers - F
The slump mold is filled with three layers of concrete - Answers - by volume
8. If the top surface of the concrete falls below the top of the slump cone while rodding
the final layer of concrete, - Answers - stop, add concrete to maintain an excess, then
continue the rod count from
where you left off.
Raise the mold vertically a distance of 12 inches - Answers - in5±2seconds
The slump of a mixture is found by - Answers - measuring the vertical distance to the
displaced original center on the top
surface of the slumped concrete.
AIR CONTENT BY PRESSURE METHOD - Answers -
It is allowable to use the Air Content by Pressure Method test to measure the air content
of fresh concrete made with - Answers - dense aggregates only
Assuming an appropriately sized coarse aggregate, it is not allowable to use the bowl of
the pressure meter to determine the density of the concrete per ASTM C138. - Answers
-F
When the coarse aggregate of a concrete mixture can be retained on a 2in. sieve, wet
sieve a sufficient amount of material for the air content test (ASTM C 231) over a
______ sieve - Answers - 1.5 in
Proper consolidation of concrete in the bowl of the pressure meter is accomplished by -
Answers - either rodding or vibration depending on the slump of the concrete
Strike off the top surface of the concrete by using - Answers - either strike off bar or
plate
The length of the tamping rod for the air pressure test shall not be less than - Answers -
16 in
The total time allowed between obtaining the first and final portions of a composite
sample is - Answers - 15 minutes
When it is necessary to wet sieve the concrete sample, wet sieving should be
performed after the individual samples are remixed into a composite sample (T or F) -
Answers - F
Tests for slump, temperature, and air content must begin within ______ minutes after
obtaining the composite sample - Answers - 5 minutes
Begin molding test specimens within ______ minutes after obtaining the composite
sample - Answers - 15 minutes
The concrete samples should be protected from - Answers - the sun, wind, and other
sources of rapid evaporation, from contamination
When test specimens are to be molded, the minimum size of sample obtained is -
Answers - 28 L (1 ft^3)
The primary objective of the sampling process is to obtain a representative sample (T or
F) - Answers - T
When sampling from a revolving drum truck mixer collect concrete from ______ portions
of the batch - Answers - 2 or more
Submerge the sensing portion of the thermometer at least ______ inches into the
concrete - Answers - 3
Gently press concrete around the thermometer such that the_______ does not
affect the reading. - Answers - ambient air temp
The thermometer must remain in the concrete during the measurement for a minimum
of ______ minutes. In addition, the temperature measurement must be completed within
_______ minutes after obtaining the sample. - Answers - 2, 5
The temperature of freshly mixed concrete is measured and recorded to the nearest
_____ - Answers - 1 degree
SLUMP TEST - Answers -
****The slump test does not provide an indication of the water content of a concrete
mixture. - Answers - F
, A slump mold can be fabricated from both plastic and metal. - Answers - T
****The length of the tamping for the slump test shall be approximately - Answers -
The slump test is applicable to concrete having a coarse aggregate up to _______ inch
in size. - Answers - 1.5 inches
The height of the slump cone is - Answers - 12 in
6. The exterior of the slump cone is tapped 10 to 15 times after rodding each layer. -
Answers - F
The slump mold is filled with three layers of concrete - Answers - by volume
8. If the top surface of the concrete falls below the top of the slump cone while rodding
the final layer of concrete, - Answers - stop, add concrete to maintain an excess, then
continue the rod count from
where you left off.
Raise the mold vertically a distance of 12 inches - Answers - in5±2seconds
The slump of a mixture is found by - Answers - measuring the vertical distance to the
displaced original center on the top
surface of the slumped concrete.
AIR CONTENT BY PRESSURE METHOD - Answers -
It is allowable to use the Air Content by Pressure Method test to measure the air content
of fresh concrete made with - Answers - dense aggregates only
Assuming an appropriately sized coarse aggregate, it is not allowable to use the bowl of
the pressure meter to determine the density of the concrete per ASTM C138. - Answers
-F
When the coarse aggregate of a concrete mixture can be retained on a 2in. sieve, wet
sieve a sufficient amount of material for the air content test (ASTM C 231) over a
______ sieve - Answers - 1.5 in
Proper consolidation of concrete in the bowl of the pressure meter is accomplished by -
Answers - either rodding or vibration depending on the slump of the concrete
Strike off the top surface of the concrete by using - Answers - either strike off bar or
plate
The length of the tamping rod for the air pressure test shall not be less than - Answers -
16 in
