T or F: After the final rodding, the sides of the slump mold should should be
tapped lightly with the tamping rod. - ANSWER--False
T or F: When raising the slump mold, it should not be rotated or twisted.
(C143/C143M - 15a, Slump of Hydraulic-Cement Concrete) - ANSWER--True
How much time is allowed for lifting the slump mold? (C143/C143M - 15a, Slump
of Hydraulic-Cement Concrete) - ANSWER--5 +/- 2 seconds
The measurement for slump is made from the top of the mold to what point is
the concrete specimen? (C143/C143M - 15a, Slump of Hydraulic-Cement
Concrete) - ANSWER--The displaced original center of the top surface of the
specimen
The slump of the concrete is measured and reported to the nearest...
(C143/C143M - 15a, Slump of Hydraulic-Cement Concrete) - ANSWER--1/4 in (5
mm)
How much time is allowed to conduct the slump test from beginning to
completion? (C143/C143M - 15a, Slump of Hydraulic-Cement Concrete) -
ANSWER--2.5 minutes
The diameter of the tamping rod used in the test method is . (C138/C138M
- 17a, Density (unit weight), yields, and air content (gravimetric) of concrete) -
ANSWER--16 mm (5/8 in) +/- 2 mm (1/16 in)
,What is the required shape of the tamping end of the rod? (C138/C138M - 17a,
Density (unit weight), yields, and air content (gravimetric) of concrete) - ANSWER-
-Rounded to a hemispherical tip
What is the required minimum frequency of the vibratos used in this testing
method? (C138/C138M - 17a, Density (unit weight), yields, and air content
(gravimetric) of concrete) - ANSWER--9000 vibrations per min (150 hz)
The outside diameter or size dimension of the vibrating element must be at least
, but not greater than . (C138/C138M - 17a, Density (unit weight), yields,
and air content (gravimetric) of concrete) - ANSWER--19 mm (0.75 in), 38 mm
(1.50 in)
T or F: A plastic container can be used for the measure in this method.
(C138/C138M - 17a, Density (unit weight), yields, and air content (gravimetric) of
concrete) - ANSWER--False, measure must be steel or other suitable metal
What is the minimum thickness of a metal striker-off plate? (C138/C138M - 17a,
Density (unit weight), yields, and air content (gravimetric) of concrete) - ANSWER-
-6 mm (1/4 in)
What is the minimum thickness for a glass or acrylic strike-off plate?
(C138/C138M - 17a, Density (unit weight), yields, and air content (gravimetric) of
concrete) - ANSWER--12 mm (1/2 in)
,What is the specific red weight of the mallet used on measures that are 14 L (0.5
ft3)? (C138/C138M - 17a, Density (unit weight), yields, and air content
(gravimetric) of concrete) - ANSWER--600 +/- 200 g (1.25 +/- 0.50 lb)
Measures other than air meter bowls used for this test must conform to ASTM
. (C138/C138M - 17a, Density (unit weight), yields, and air content
(gravimetric) of concrete) - ANSWER--C29/C29M
Air meter bowls used for this test must conform to ASTM and be calibrated
for volume according to ASTM . (C138/C138M - 17a, Density (unit weight),
yields, and air content (gravimetric) of concrete) - ANSWER--C231/C231M,
C29/C29M
The concrete sample must be obtained in accodance with what ASTM method?
(C138/C138M - 17a, Density (unit weight), yields, and air content (gravimetric) of
concrete) - ANSWER--C172/C172M
What method of consolidation must be used when the slump is greater than 75
mm (3 in) (C138/C138M - 17a, Density (unit weight), yields, and air content
(gravimetric) of concrete) - ANSWER--Rodding
What method of consolidation must be used when the slump is less than 1 in. (25
mm]? (C138/C138M - 17a, Density (unit weight), yields, and air content
(gravimetric) of concrete) - ANSWER--Vibration
, If rodding is the method of consolidation being used, the measure must be filled
in how many layers? (C138/C138M - 17a, Density (unit weight), yields, and air
content (gravimetric) of concrete) - ANSWER--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? (C138/C138M - 17a, Density (unit
weight), yields, and air content (gravimetric) of concrete) - ANSWER--25
When rodding the middle and the top layers, the tamping rod should penetrate
into the layer below approximately . (C138/C138M - 17a, Density (unit
weight), yields, and air content (gravimetric) of concrete) - ANSWER--25 mm (1 in)
If vibration is the method of consolidation, the measure must be filled in
approximately equal layers. (C138/C138M - 17a, Density (unit weight), yields, and
air content (gravimetric) of concrete) - ANSWER--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? (C138/C138M - 17a, Density (unit
weight), yields, and air content (gravimetric) of concrete) - ANSWER--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. (C138/C138M - 17a, Density (unit weight),
yields, and air content (gravimetric) of concrete) - ANSWER--3 mm (1/8 in)
