ACI GRADE 1 WRITTEN EXAM 2025
QUESTIONS AND ANSWERS
The temp. measuring device shall be capable of accurately measuring the temp. of freshly
mixed concrete to ____ throughout a range of ____. - ANS 1 Degree F, 30-120 Degrees F
A composite sample of concrete is required even if the only purpose for obtaining the sample is
to determine the temp. T or F? - ANS False
C172/C172M covers sampling from five type of equipment which are___, ___, ___, ___, &
____? - ANS revolving drum, stationary, paving, continuous, & open top
The mold for making the slump test is in the shape of ____. - ANS the frustum of a cone
The surface on which the slump mold will be placed must be ____. - ANS Flat, moist non-
absorbent, & rigid
How deep should the tamping rod penetrate each layer? - ANS Rod each layer throughout
it's depth , on second & final layer the rod should penetrate into the previous layer
approximately 1 in.
Prior to lifting the mold, concrete must be removed from ____. - ANS the area surrounding
the base of the mold
What is the minimum frequency of the vibrator used in Test Method C138/C138M -
ANS 9000 Vibrations/Min., 150 Hertz
1 Copyright ©BRIGHSTARS ALL RIGHTS RESERVED 2025
, What is the minimum thickness of a metal strike-off plate used in Test Method C138/C138M? -
ANS 1/4 in.
What is the minimum thickness of a glass/acrylic strike-off plate used in Test Method
C138/C138M? - ANS 1/2 in.
Measures other than air meter bowls used for Test Method C138/C138M must conform to Test
Method ___. - ANS C29/C29M
Air meter bowls used for Test Method C138/C138M must conform to Test Method ___ and be
calibrated for volume according to Test Method ___. - ANS C231, C29
The pressure method of determining air content can be used on concrete containing ___ ____
aggregate. - ANS relatively dense
The pressure method of determining air content cannot be used on concrete containing the
following types of aggregate: ___, ___, & ___. - ANS light weight, air-cooled blast furnace
slag, & aggregate of high porosity
What is the minimum allowable capacity of the measuring bowl used in Test Method
C231/C231M? - ANS 6L (0.2ft^3)
What are the required characteristics of the tamping rod used in Test Method C231/C231M? -
ANS Round, straight steel rod, w/ a 16 mm (5/8 in) +-2 mm (1/16 in) diameter, length of at
least 100 mm (4 in) greater than the depth of the measuring bowl, but not greater than 600
mm (24 in) in overall length w/ the tamping end rounded to a hemispherical tip of the same
diameter as the rod
What is the specified size of the mallet required for Test Method C231/C231M when the
measuring bowl has a capacity of 14 L (0.5 ft^3) or less? - ANS 1 & 1/4 lbs +-0.5 lbs
The maximum size aggregate allowed for Test Method C231/C231M is ___. - ANS 2 in
2 Copyright ©BRIGHSTARS ALL RIGHTS RESERVED 2025
QUESTIONS AND ANSWERS
The temp. measuring device shall be capable of accurately measuring the temp. of freshly
mixed concrete to ____ throughout a range of ____. - ANS 1 Degree F, 30-120 Degrees F
A composite sample of concrete is required even if the only purpose for obtaining the sample is
to determine the temp. T or F? - ANS False
C172/C172M covers sampling from five type of equipment which are___, ___, ___, ___, &
____? - ANS revolving drum, stationary, paving, continuous, & open top
The mold for making the slump test is in the shape of ____. - ANS the frustum of a cone
The surface on which the slump mold will be placed must be ____. - ANS Flat, moist non-
absorbent, & rigid
How deep should the tamping rod penetrate each layer? - ANS Rod each layer throughout
it's depth , on second & final layer the rod should penetrate into the previous layer
approximately 1 in.
Prior to lifting the mold, concrete must be removed from ____. - ANS the area surrounding
the base of the mold
What is the minimum frequency of the vibrator used in Test Method C138/C138M -
ANS 9000 Vibrations/Min., 150 Hertz
1 Copyright ©BRIGHSTARS ALL RIGHTS RESERVED 2025
, What is the minimum thickness of a metal strike-off plate used in Test Method C138/C138M? -
ANS 1/4 in.
What is the minimum thickness of a glass/acrylic strike-off plate used in Test Method
C138/C138M? - ANS 1/2 in.
Measures other than air meter bowls used for Test Method C138/C138M must conform to Test
Method ___. - ANS C29/C29M
Air meter bowls used for Test Method C138/C138M must conform to Test Method ___ and be
calibrated for volume according to Test Method ___. - ANS C231, C29
The pressure method of determining air content can be used on concrete containing ___ ____
aggregate. - ANS relatively dense
The pressure method of determining air content cannot be used on concrete containing the
following types of aggregate: ___, ___, & ___. - ANS light weight, air-cooled blast furnace
slag, & aggregate of high porosity
What is the minimum allowable capacity of the measuring bowl used in Test Method
C231/C231M? - ANS 6L (0.2ft^3)
What are the required characteristics of the tamping rod used in Test Method C231/C231M? -
ANS Round, straight steel rod, w/ a 16 mm (5/8 in) +-2 mm (1/16 in) diameter, length of at
least 100 mm (4 in) greater than the depth of the measuring bowl, but not greater than 600
mm (24 in) in overall length w/ the tamping end rounded to a hemispherical tip of the same
diameter as the rod
What is the specified size of the mallet required for Test Method C231/C231M when the
measuring bowl has a capacity of 14 L (0.5 ft^3) or less? - ANS 1 & 1/4 lbs +-0.5 lbs
The maximum size aggregate allowed for Test Method C231/C231M is ___. - ANS 2 in
2 Copyright ©BRIGHSTARS ALL RIGHTS RESERVED 2025
