ASTM C143/C143M - Standard Test Method for Slump of Hydraulic Concrete Flashcards
Maximum aggregate size for slump testing is ___?
1.5 inches
Dimensions of the slump cone are?
4” diameter @ top
8” diameter @ bottom
12” high
Slump cone can be made of which materials?
Metal or Plastic
Metal slump cone thickness is ____ ?
Plastic slump cone thickness is ____?
.06 inches (1.5 mm) for metal
.125 inches (3 mm) for plastic
Sample of concrete for use in performing the slump test must be obtained in accordance with which ASTM practice?
ASTM C172
Slump cone is filled in ___ layers of equal ______?
3 layers of equal VOLUME
How deep should the bottom layer of concrete be?
How deep should the second layer of concrete be?
bottom layer = 2 5/8 inches
second layer = 6 1/8 inches
Interior of slump cone must be ________ prior to inserting concrete into the mold.
Dampened
If concrete drops below the top of the slump mold when rodding the final layer, what should you do?
Stop rodding, fill the cone with more of the sample and then continue rodding where you left off
Strike off the top of the cone with which device?
a - Tamping Rod
b - Strike-off bar
c - Strike-off plate
a - Tamping rod
Strike off the top of the cone using a ______ motion?
a - Sawing
b - Twisting
c - Both
c - Both
If a decided falling away, or shearing off of concrete from one side or portion of mass occurs, disregard the test and ____________________?
Make a new test from the same sample portion.
If two consecutive tests on a sample of concrete show a falling away or shearing off of a portion of the concrete from the mass of the specimen, the concrete probably lacks necessary _______ and ________ for the slump test to be applicable.
Plasticity
Cohesiveness
TRUE or FALSE:
When rodding the bottom layer, tamping rod must be angled to uniformly distribute the strokes
True
TRUE or FALSE:
Sides of the cone need to be tapped with open hand after consolidation of each later
False - Slump cone does not require tapping/striking
To determine slump, measure vertical distance between top of cone and ______________?
Displaced original center of top surface
What are the two ways of holding down the slump cone?
Feet
Clamps
Slump cone should be raised carefully, vertically upward, in a steady motion and take no more than _______ seconds
5 [+/- 2] seconds
Elapsed time between start of filling cone and the removal of the cone should not exceed ____ minutes?
2 1/2 minutes
Slump is measured to the nearest ____
1/4 inch
Rod each layer of concrete ____ times
25
Interior of slump cone should be (1)______, have no (2)______, and be free from (3)_____ or (4)_____.
Choose from the list below: a - Moisture b - Dents c - Smooth d - New e - Projections f - Aggregates g - Seems h - Plastic
(1) = a - Smooth
(2) = b - Seems
(3) = c - Projections
(4) = b - Dents
TRUE or FALSE:
Place the slump mold on a surface that is rigid, flat, level, moist, nonabsorbent, free of vibration and that is a minimum of 2” bigger than the base of the mold
False - the surface needs to be rigid, flat, level, moist, nonabsorbent, free of vibration and that is LARGE ENOUGH TO CONTAIN ALL OF THE SLUMPED CONCRETE.
Slump form to be in the shape of ____________
Frustum of a cone
To measure the slump, the measuring device must be at least _____ inches long with increments of at least ____ inch.
12 inches long
Increments of at least 1/4 inch
When filling the cone with a scoop, should you:
A - dump the concrete directly into the top hole of the mold at an initial depth of 2 5/8”
or
B - Move the scoop around the perimeter of the mold opening to ensure an even distribution of the concrete to an initial depth of 2 5/8”
B - Move the scoop around the perimeter of the mold opening to ensure an even distribution of the concrete to an initial depth of 2 5/8”
