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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
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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 2 / 3
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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
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