ACI Certification Exam
ASTM C172 covers sampling from stationary, paving and truck mixers, and from agitating and
non-agitating equipment used to transport central-mixed concrete. - ANS-True
When the concrete contains large aggregate, the testing technician should wet-sieve the sample
before making unit weight tests for use in yield computations. - ANS-False
Samples should be taken before 10% or after 90% of the batch has been discharged. -
ANS-False
Samples smaller than 28L (1 cu.ft.) are allowed on routine air content, temperature, and slump
tests. - ANS-True
Tests for slump and air content must be started within ____________ after obtaining the final
portion of the composite sample. - ANS-5 Minutes
Start molding strength test specimens within ________ after fabricating the composite sample. -
ANS-15 Minutes
How do you regulate the rate of discharge of the batch from the revolving truck drum mixer or
agitator? - ANS-By the rate of revolution of the drum
The mold is in the shape of a ___________________. - ANS-Frustrum of a Cone
The top diameter of a slump cone is ______ and the diameter at the base is ________. -
ANS-4", 8"
While the technician is checking the slump of the concrete, there is a decided falling away or
shearing off of the concrete from one side of the sample. What should the technician do? -
ANS-Disregard the test and retest on another portion of the sample
The mold is filled in three equal layers by volume, which makes the first third at _______, and
the second third at ________. - ANS-2 5/8, 6 1/8
The maximum size of aggregate allowed for ASTM C143 is _________. - ANS-1 ½"
When rodding the second and third layers the rod should penetrate through the layer and into
the previous layer________. - ANS-1"
The slump of the concrete was determined to be 4 5/16" what should be recorded as the slump?
- ANS-4 1/4"
, What is the difference allowed by ACI when certifying an individual test using a plastic slump
cone vs. a metal slump cone? - ANS-.5"
The sides of the slump mold should be lightly tapped to consolidate the concrete in the mold -
ANS-False
When rodding the final lift additional concrete must be added to keep excess concrete above
the top of the mold at all times - ANS-True
ASTM C 1064 defines the maximum recommended temperature for concrete. - ANS-False
The temperature test method must be complete with in _________ after obtaining the sample. -
ANS-5 Minutes
Each temperature-measuring device should be calibrated ________, or whenever there is a
question of _________. - ANS-Annually, Accuracy
When determining the temperature of fresh concrete, what is the minimum amount of concrete
cover in all directions around the sensor of the TMD? - ANS-3"
When the concrete contains a nominal maximum size of aggregate greater than 3 inches, it may
require __________ before the temperature is stabilized after mixing. - ANS-20 Minutes
After strike off of the measure used to determine density, a small quantity of concrete may be
added to correct a deficiency? - ANS-False
If using any strike off plate the plate must be at least 1 inch greater than the diameter of the
measure with which it is being used. - ANS-False
If rodding is the method of consolidation being used in C138, the measure must be filled in how
many layers? - ANS-3
What is the required shape at the end of the tamping rod? - ANS-rounded to a hemispherical tip
After consolidation of the final layer, the concrete is ½ inch above the top of the measure, what
should be done? - ANS-remove excess concrete with a scoop or trowel
According to ASTM C 138 what is the density of the following concrete batch?
Mass of Measure 7.4 lbs
Mass of Measure w/ Concrete 44.5 lbs
Volume of Measure .254 CF - ANS-146.06 lb/cf = (44.5-7.4)/0.254
ASTM C172 covers sampling from stationary, paving and truck mixers, and from agitating and
non-agitating equipment used to transport central-mixed concrete. - ANS-True
When the concrete contains large aggregate, the testing technician should wet-sieve the sample
before making unit weight tests for use in yield computations. - ANS-False
Samples should be taken before 10% or after 90% of the batch has been discharged. -
ANS-False
Samples smaller than 28L (1 cu.ft.) are allowed on routine air content, temperature, and slump
tests. - ANS-True
Tests for slump and air content must be started within ____________ after obtaining the final
portion of the composite sample. - ANS-5 Minutes
Start molding strength test specimens within ________ after fabricating the composite sample. -
ANS-15 Minutes
How do you regulate the rate of discharge of the batch from the revolving truck drum mixer or
agitator? - ANS-By the rate of revolution of the drum
The mold is in the shape of a ___________________. - ANS-Frustrum of a Cone
The top diameter of a slump cone is ______ and the diameter at the base is ________. -
ANS-4", 8"
While the technician is checking the slump of the concrete, there is a decided falling away or
shearing off of the concrete from one side of the sample. What should the technician do? -
ANS-Disregard the test and retest on another portion of the sample
The mold is filled in three equal layers by volume, which makes the first third at _______, and
the second third at ________. - ANS-2 5/8, 6 1/8
The maximum size of aggregate allowed for ASTM C143 is _________. - ANS-1 ½"
When rodding the second and third layers the rod should penetrate through the layer and into
the previous layer________. - ANS-1"
The slump of the concrete was determined to be 4 5/16" what should be recorded as the slump?
- ANS-4 1/4"
, What is the difference allowed by ACI when certifying an individual test using a plastic slump
cone vs. a metal slump cone? - ANS-.5"
The sides of the slump mold should be lightly tapped to consolidate the concrete in the mold -
ANS-False
When rodding the final lift additional concrete must be added to keep excess concrete above
the top of the mold at all times - ANS-True
ASTM C 1064 defines the maximum recommended temperature for concrete. - ANS-False
The temperature test method must be complete with in _________ after obtaining the sample. -
ANS-5 Minutes
Each temperature-measuring device should be calibrated ________, or whenever there is a
question of _________. - ANS-Annually, Accuracy
When determining the temperature of fresh concrete, what is the minimum amount of concrete
cover in all directions around the sensor of the TMD? - ANS-3"
When the concrete contains a nominal maximum size of aggregate greater than 3 inches, it may
require __________ before the temperature is stabilized after mixing. - ANS-20 Minutes
After strike off of the measure used to determine density, a small quantity of concrete may be
added to correct a deficiency? - ANS-False
If using any strike off plate the plate must be at least 1 inch greater than the diameter of the
measure with which it is being used. - ANS-False
If rodding is the method of consolidation being used in C138, the measure must be filled in how
many layers? - ANS-3
What is the required shape at the end of the tamping rod? - ANS-rounded to a hemispherical tip
After consolidation of the final layer, the concrete is ½ inch above the top of the measure, what
should be done? - ANS-remove excess concrete with a scoop or trowel
According to ASTM C 138 what is the density of the following concrete batch?
Mass of Measure 7.4 lbs
Mass of Measure w/ Concrete 44.5 lbs
Volume of Measure .254 CF - ANS-146.06 lb/cf = (44.5-7.4)/0.254
