ACI Concrete Strength Testing Technician -
Practice C617/C617M,
C1231/C1231M,C39/C39M {latest 2026 -
2027 update} questions and answers 100%
correct
When qualifying unbonded caps, strength below ____ of the average obtained from
bonded caps is considered unacceptable - correct answer 98%
T or F: Practice C1231 contains step by step procedures for aligning the specimens in
the testing machine through complete failure of the cylinder. - correct answer F
The pads used in this practice must be ____ thick, and the diameter shall not be more
than _____ smaller that the inside diameter of the retaining ring. - correct answer 1/2",
1/16"
The height of the metal retaining ring must be ____ - correct answer 1"
,The inside diameter of the retaining ring shall not be less than _____ or greater than
____ of the diameter of the cylinder. - correct answer 102% , 107%
Depressions in the ends of cylinders that exceed _____ must be corrected by sawing or
grinding prior to testing. - correct answer 0.2"
Qualification tests on an unbonded capping system must be repeated whenever there
are changes in __________,____________, or ________ - correct answer design, dimensions,
pad composition, change in shore a hardness by more than 5 units
T or F: This test method measures the compressive strength of cylindrical concrete
specimens that have a density of less than 50 lb/ft^3 - correct answer False; have
density of more than 800 kg/m^3 [50 lb/ft^3]
, The test method of ASTM C39/C39M consists of applying a compressive load to molded
cylinders or cores at any rate until failure occurs. True or False? - correct answer
False; a prescribed rate
Results obtained from the compressive strength test method will depend on many
things, such as the size and _____ of the specimen, batching, _____ procedures, the age,
temperature, and _____ conditions during curing. - correct answer Shape, mixing,
moisture
This test method is used to determine _____ of cylindrical specimens. - correct answer
Compressive strength
The calibration of the testing machines must be verified under four conditions: at least
_____ upon original installation or after _____., after making _____ or adjustments, and
Practice C617/C617M,
C1231/C1231M,C39/C39M {latest 2026 -
2027 update} questions and answers 100%
correct
When qualifying unbonded caps, strength below ____ of the average obtained from
bonded caps is considered unacceptable - correct answer 98%
T or F: Practice C1231 contains step by step procedures for aligning the specimens in
the testing machine through complete failure of the cylinder. - correct answer F
The pads used in this practice must be ____ thick, and the diameter shall not be more
than _____ smaller that the inside diameter of the retaining ring. - correct answer 1/2",
1/16"
The height of the metal retaining ring must be ____ - correct answer 1"
,The inside diameter of the retaining ring shall not be less than _____ or greater than
____ of the diameter of the cylinder. - correct answer 102% , 107%
Depressions in the ends of cylinders that exceed _____ must be corrected by sawing or
grinding prior to testing. - correct answer 0.2"
Qualification tests on an unbonded capping system must be repeated whenever there
are changes in __________,____________, or ________ - correct answer design, dimensions,
pad composition, change in shore a hardness by more than 5 units
T or F: This test method measures the compressive strength of cylindrical concrete
specimens that have a density of less than 50 lb/ft^3 - correct answer False; have
density of more than 800 kg/m^3 [50 lb/ft^3]
, The test method of ASTM C39/C39M consists of applying a compressive load to molded
cylinders or cores at any rate until failure occurs. True or False? - correct answer
False; a prescribed rate
Results obtained from the compressive strength test method will depend on many
things, such as the size and _____ of the specimen, batching, _____ procedures, the age,
temperature, and _____ conditions during curing. - correct answer Shape, mixing,
moisture
This test method is used to determine _____ of cylindrical specimens. - correct answer
Compressive strength
The calibration of the testing machines must be verified under four conditions: at least
_____ upon original installation or after _____., after making _____ or adjustments, and
