ACI CERTIFICATION EXAM QUESTIONS
WITH VERIFIED ANSWERS 2025/2026
ASTM C172 covers sampling from stationary, paving and truck mixers, and from agitating and
non-agitating equipment used to transport central-mixed concrete. - CORRECT ANSWER -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. - CORRECT ANSWER -False
Samples should be taken before 10% or after 90% of the batch has been discharged. - CORRECT
ANSWER -False
Samples smaller than 28L (1 cu.ft.) are allowed on routine air content, temperature, and slump
tests. - CORRECT ANSWER -True
Tests for slump and air content must be started within after obtaining the final
portion of the composite sample. - CORRECT ANSWER -5 Minutes
Start molding strength test specimens within after fabricating the composite sample.
- CORRECT ANSWER -15 Minutes
How do you regulate the rate of discharge of the batch from the revolving truck drum mixer or
agitator? - CORRECT ANSWER -By the rate of revolution of the drum
The mold is in the shape of a . - CORRECT ANSWER -Frustrum of a Cone
The top diameter of a slump cone is and the diameter at the base is .-
CORRECT ANSWER -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? -
CORRECT ANSWER -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 . - CORRECT ANSWER -2 5/8, 6 1/8
The maximum size of aggregate allowed for ASTM C143 is . - CORRECT ANSWER -1 ½"
When rodding the second and third layers the rod should penetrate through the layer and into
the previous layer . - CORRECT ANSWER -1"
The slump of the concrete was determined to be 4 5/16" what should be recorded as the
slump? - CORRECT ANSWER -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? - CORRECT ANSWER -.5"
The sides of the slump mold should be lightly tapped to consolidate the concrete in the mold -
CORRECT ANSWER -False
When rodding the final lift additional concrete must be added to keep excess concrete above
the top of the mold at all times - CORRECT ANSWER -True
ASTM C 1064 defines the maximum recommended temperature for concrete. - CORRECT
ANSWER -False
WITH VERIFIED ANSWERS 2025/2026
ASTM C172 covers sampling from stationary, paving and truck mixers, and from agitating and
non-agitating equipment used to transport central-mixed concrete. - CORRECT ANSWER -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. - CORRECT ANSWER -False
Samples should be taken before 10% or after 90% of the batch has been discharged. - CORRECT
ANSWER -False
Samples smaller than 28L (1 cu.ft.) are allowed on routine air content, temperature, and slump
tests. - CORRECT ANSWER -True
Tests for slump and air content must be started within after obtaining the final
portion of the composite sample. - CORRECT ANSWER -5 Minutes
Start molding strength test specimens within after fabricating the composite sample.
- CORRECT ANSWER -15 Minutes
How do you regulate the rate of discharge of the batch from the revolving truck drum mixer or
agitator? - CORRECT ANSWER -By the rate of revolution of the drum
The mold is in the shape of a . - CORRECT ANSWER -Frustrum of a Cone
The top diameter of a slump cone is and the diameter at the base is .-
CORRECT ANSWER -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? -
CORRECT ANSWER -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 . - CORRECT ANSWER -2 5/8, 6 1/8
The maximum size of aggregate allowed for ASTM C143 is . - CORRECT ANSWER -1 ½"
When rodding the second and third layers the rod should penetrate through the layer and into
the previous layer . - CORRECT ANSWER -1"
The slump of the concrete was determined to be 4 5/16" what should be recorded as the
slump? - CORRECT ANSWER -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? - CORRECT ANSWER -.5"
The sides of the slump mold should be lightly tapped to consolidate the concrete in the mold -
CORRECT ANSWER -False
When rodding the final lift additional concrete must be added to keep excess concrete above
the top of the mold at all times - CORRECT ANSWER -True
ASTM C 1064 defines the maximum recommended temperature for concrete. - CORRECT
ANSWER -False
