ACI Concrete Field Testing Technician
- Grade I (40th Edition) Test
Collecting a representative sample of concrete to be tested is as important as executing
the test methods to obtain __________. - ANSWER-accurate results
This practice covers sampling from four types of equipment, which are ________,
________, ________, and ________. - ANSWER-stationary mixers, paving mixers,
revolving truck mixers, continuous mixers
The elapsed time between obtaining the first and final portions of a composite sample
shall not exceed ______. - ANSWER-15 minutes
Portions of a composite sample shall be thoroughly remixed before beginning tests on
the sample. True or False? - ANSWER-True
Start tests for slump, temperature, and air content within ________ after obtaining the
final portion of the composite sample. - ANSWER-5 minutes
Start molding specimens for strength tests within ________ after fabricating the
composite sample. - ANSWER-15 minutes
The concrete sample must be protected from contamination and _________. -
ANSWER-rapid evaporation
The minimum size sample for making strength test specimens is _________. -
ANSWER-1 cubic feet [28 L]
When sampling from a stationary mixer, the batch must be sampled at ________ or
more regularly spaced intervals during discharge of the middle portion of the batch. -
ANSWER-2
When sampling from a paving mixer, obtain samples from at least ________ different
portions of the pile and combine them into one composite sample for test purposes. -
ANSWER-5
When sampling from a revolving truck mixer, sample the concrete by collecting
________ or more portions taken at regularly spaced intervals during discharge of the
middle portion of the batch. - ANSWER-2
, Concrete samples from a truck mixer must be obtained before any water or admixtures
are added to the mixer at the job site. True or False? - ANSWER-False
When the concrete contains aggregate larger than that permitted for a particular test
method, the sample of concrete must be ________ before making the test. - ANSWER-
wet screened
The stem of the thermometer is submerged a minimum of ________ into the freshly
mixed concrete. - ANSWER-3 inches [75 mm]
The thermometer shall be capable of accurately measuring the temperature of freshly
mixed concrete to ________ throughout a range of ________. - ANSWER-+/- 1F [0.5
C]; a range of 30 - 120F [0 - 50 C]
The thermometer shall be verified within _________. - ANSWER-at least one year of its
current use
The temperature of concrete may be measured in a wheelbarrow. True or False? -
ANSWER-True
When raising the slump mold, it should not be rotated or twisted. True or False? -
ANSWER-True
How much time is allowed for lifting the slump mold? - ANSWER-5 +/- 2 seconds (3 - 7
seconds)
The measurement for slump is made from the top of the mold to what point of the
concrete specimen? - ANSWER-the displaced original center of the top surface of the
specimen/slump
The slump of the concrete is measured and reported to the nearest _________. -
ANSWER-quarter inch (1/4 inch [5 mm])
How much time is allowed to conduct the slump test from beginning to completion? -
ANSWER-2.5 minutes
The length of the tamping rod used in this test method is _________. - ANSWER-at
least 4 inches [100 mm] taller than the height of the measure but no more than 24
inches [600 mm] in overall length
What is the required shape of the tamping end of the rod? - ANSWER-rounded to a
hemispherical tip
What is the required minimum frequency of the vibrator used in this test method? -
ANSWER-9000 vibrations per minute [150 Hz]
- Grade I (40th Edition) Test
Collecting a representative sample of concrete to be tested is as important as executing
the test methods to obtain __________. - ANSWER-accurate results
This practice covers sampling from four types of equipment, which are ________,
________, ________, and ________. - ANSWER-stationary mixers, paving mixers,
revolving truck mixers, continuous mixers
The elapsed time between obtaining the first and final portions of a composite sample
shall not exceed ______. - ANSWER-15 minutes
Portions of a composite sample shall be thoroughly remixed before beginning tests on
the sample. True or False? - ANSWER-True
Start tests for slump, temperature, and air content within ________ after obtaining the
final portion of the composite sample. - ANSWER-5 minutes
Start molding specimens for strength tests within ________ after fabricating the
composite sample. - ANSWER-15 minutes
The concrete sample must be protected from contamination and _________. -
ANSWER-rapid evaporation
The minimum size sample for making strength test specimens is _________. -
ANSWER-1 cubic feet [28 L]
When sampling from a stationary mixer, the batch must be sampled at ________ or
more regularly spaced intervals during discharge of the middle portion of the batch. -
ANSWER-2
When sampling from a paving mixer, obtain samples from at least ________ different
portions of the pile and combine them into one composite sample for test purposes. -
ANSWER-5
When sampling from a revolving truck mixer, sample the concrete by collecting
________ or more portions taken at regularly spaced intervals during discharge of the
middle portion of the batch. - ANSWER-2
, Concrete samples from a truck mixer must be obtained before any water or admixtures
are added to the mixer at the job site. True or False? - ANSWER-False
When the concrete contains aggregate larger than that permitted for a particular test
method, the sample of concrete must be ________ before making the test. - ANSWER-
wet screened
The stem of the thermometer is submerged a minimum of ________ into the freshly
mixed concrete. - ANSWER-3 inches [75 mm]
The thermometer shall be capable of accurately measuring the temperature of freshly
mixed concrete to ________ throughout a range of ________. - ANSWER-+/- 1F [0.5
C]; a range of 30 - 120F [0 - 50 C]
The thermometer shall be verified within _________. - ANSWER-at least one year of its
current use
The temperature of concrete may be measured in a wheelbarrow. True or False? -
ANSWER-True
When raising the slump mold, it should not be rotated or twisted. True or False? -
ANSWER-True
How much time is allowed for lifting the slump mold? - ANSWER-5 +/- 2 seconds (3 - 7
seconds)
The measurement for slump is made from the top of the mold to what point of the
concrete specimen? - ANSWER-the displaced original center of the top surface of the
specimen/slump
The slump of the concrete is measured and reported to the nearest _________. -
ANSWER-quarter inch (1/4 inch [5 mm])
How much time is allowed to conduct the slump test from beginning to completion? -
ANSWER-2.5 minutes
The length of the tamping rod used in this test method is _________. - ANSWER-at
least 4 inches [100 mm] taller than the height of the measure but no more than 24
inches [600 mm] in overall length
What is the required shape of the tamping end of the rod? - ANSWER-rounded to a
hemispherical tip
What is the required minimum frequency of the vibrator used in this test method? -
ANSWER-9000 vibrations per minute [150 Hz]
