Questions with correct answers already graded A+
2024/25 latest
What is the minimum thickness for a glass or acrylic strike-off plate?
1/2 in. [12 mm]
What is the specified weight of the mallet used on measures that are 0.5 ft^3 [14 L] or smaller?
1.25 +- 0.50 lb. [600 +- 200 g]
Measures other than air meter bowls used for this test must conform to ASTM _____.
C29
Air meter bowls used for this test must conform to ASTM _____ and be calibrated for volume according to ASTM
_____.
C231, C29
The concrete sample must be obtained by what ASTM method?
C172
What method of consolidation must be used when the slump is greater than 3 in? [75 mm]?
Rodding
What method of consolidation must be used when the slump is less than 1 in. (25 mm]?
Vibration
,If rodding is the method of consolidation being used, the measure must be filled in how many layers?
3
For a measure of 0.5 ft^3 [14 L], what is the required number of strokes of the tamping rod for consolidation of
each layer?
25
.
When rodding the middle and the top layers, the tamping rod should penetrate the layer below approximately
_____.
1 in. [25 mm]
If vibration is the method of consolidation, the measure must be filled in _____ approximately equal layers.
2
If, after consolidation of the final layer, the concrete level is 1/2 in. (13 mm) above the top of the measure, what
should be done?
Remove a representative portion of the excess concrete with a trowel or scoop
After consolidation of the final layer, an excess of concrete ____ above the top of the measure is considered
optimum.
1/8 in. [3 mm]
The temperature measuring device shall have the capacity to measure the temperature of freshly mixed
concrete to +- _____ degrees F [+- _____ C] throughout a range of _____.
, 1 degree F [0.5 C], 30 degrees F to 120 F [0 C to 50 C]
The temperature measuring device shall be calibrated _____, or whenever there is a question of _____.
Annually, accuracy
The temperature of concrete may be measured in a wheelbarrow. True or False?
True
The temperature of concrete may be measured in a wall form. True of False
True
A composite sample of concrete is required even if the only purpose for obtaining the sample is to determine
temperature. True of False?
False
What must be done to the sample container before sampling the concrete?
Dampen (with water)
What must be done to the concrete surrounding the temperature measuring device after the device is
submerged in the fresh concrete.
Gently press the concrete around the temperature-measuring device at the surface of the concrete
How long must the temperature measuring device remain in the freshly mixed concrete?
At least 2 minutes but not more than 5 minutes