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ASTM ACI CONCRETE STRENGTH TESTING
LAB TECHNICIAN EXAM NEWEST 2025 ACTUAL
EXAM 100 QUESTIONS AND CORRECT
DETAILED ANSWERS (VERIFIED ANSWERS) |A+
GRADED
The pads used in this practice must be _____ thick, and the the
diameter shall not be more than _____ smaller than the inside
diameter of the retaining ring. - ANSWER-3 +- 2mm (1/2" +-
1/16"), 2mm (1/16")
The height of the metal retaining ring must be ______. -
ANSWER-25 +- 3mm (1 in +- .1 in)
The inside diameter of the retaining rings shall not be less than
______ or greater than _______ of the diameter of the cylinder -
ANSWER-102 %, 107 %
Neither end of the cylinder shall depart from perpendicularity by
more than ________ degrees - ANSWER-.5 degrees
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Depressions in the ends of cylinders that exceed _______ must
be corrected by sawing or grinding prior to testing. - ANSWER-
5mm (.2 in)
pads that have cracks or splits exceeding ______ in _____
regardless of their _______ must be replaced - ANSWER-3/8 in
(10mm), length, depth
Rotation of the movable portion of the testing machine's
spherically seated bearing block as it is brought to bear on the
upper retaining ring is not necessary when using pad caps, since
the pad's deformation will compensate and provide uniform
loading. True or false? - ANSWER-False
qualification tests on an unbonded capping system must be
repeated whenever there are changes in: (3 answers) -
ANSWER-the design or dimensions of the retaining rings, pad
composition or thickness, or the shore A hardness by more than
5 units
After application of the load, but before ______ of the
anticipated specimen strength, check to see that the axis of the
cylinder is vertical within a tolerance of _______. - ANSWER-
50 %, 1/8 in 12
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ASTM standard dealing with compressive strength of cylindrical
concrete specimens - ANSWER-C39
ASTM C39 measures the compressive strength of cylindrical
concrete specimens that weigh less than 800 kg/m3 (50 lb/ft3).
True or false - ANSWER-False.. weigh more than
ASTM C39 consists of applying a compressive axial load to
molded cylinders or cores at any rate until failure occurs. True or
false? - ANSWER-False, Specified 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. - ANSWER-shape, mixing,
moisture
ASTM C39 is used to determine ____ _____ of cylindrical
specimens. - ANSWER-Compressive Strength
The calibration of the testing machines must be verified under 4
conditions: at least ____, upon original installation, or after
ASTM ACI CONCRETE STRENGTH TESTING
LAB TECHNICIAN EXAM NEWEST 2025 ACTUAL
EXAM 100 QUESTIONS AND CORRECT
DETAILED ANSWERS (VERIFIED ANSWERS) |A+
GRADED
The pads used in this practice must be _____ thick, and the the
diameter shall not be more than _____ smaller than the inside
diameter of the retaining ring. - ANSWER-3 +- 2mm (1/2" +-
1/16"), 2mm (1/16")
The height of the metal retaining ring must be ______. -
ANSWER-25 +- 3mm (1 in +- .1 in)
The inside diameter of the retaining rings shall not be less than
______ or greater than _______ of the diameter of the cylinder -
ANSWER-102 %, 107 %
Neither end of the cylinder shall depart from perpendicularity by
more than ________ degrees - ANSWER-.5 degrees
,2|Page
Depressions in the ends of cylinders that exceed _______ must
be corrected by sawing or grinding prior to testing. - ANSWER-
5mm (.2 in)
pads that have cracks or splits exceeding ______ in _____
regardless of their _______ must be replaced - ANSWER-3/8 in
(10mm), length, depth
Rotation of the movable portion of the testing machine's
spherically seated bearing block as it is brought to bear on the
upper retaining ring is not necessary when using pad caps, since
the pad's deformation will compensate and provide uniform
loading. True or false? - ANSWER-False
qualification tests on an unbonded capping system must be
repeated whenever there are changes in: (3 answers) -
ANSWER-the design or dimensions of the retaining rings, pad
composition or thickness, or the shore A hardness by more than
5 units
After application of the load, but before ______ of the
anticipated specimen strength, check to see that the axis of the
cylinder is vertical within a tolerance of _______. - ANSWER-
50 %, 1/8 in 12
, 3|Page
ASTM standard dealing with compressive strength of cylindrical
concrete specimens - ANSWER-C39
ASTM C39 measures the compressive strength of cylindrical
concrete specimens that weigh less than 800 kg/m3 (50 lb/ft3).
True or false - ANSWER-False.. weigh more than
ASTM C39 consists of applying a compressive axial load to
molded cylinders or cores at any rate until failure occurs. True or
false? - ANSWER-False, Specified 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. - ANSWER-shape, mixing,
moisture
ASTM C39 is used to determine ____ _____ of cylindrical
specimens. - ANSWER-Compressive Strength
The calibration of the testing machines must be verified under 4
conditions: at least ____, upon original installation, or after
