The sensor of the temperature measuring device shall be submerged a minimum of _____ in.
[_____mm] into the freshly mixed concrete. - *answers * 3 in. [75 mm]
The temperature measuring device shall have the capacity to measure the temperature of
freshly mixed concrete to +- _____ degrees F [+- _____ C] throughout a range of _____. -
*answers * 1 degree F [0.5 C], 30 degrees F to 120 F [0 C to 50 C]
The temperature measuring device shall be calibrated _____, or whenever there is a question of
_____. - *answers * Annually, accuracy
The temperature of concrete may be measured in a wheelbarrow. True or False? - *answers *
True
The temperature of concrete may be measured in a wall form. True or False - *answers * True
A composite sample of concrete is required even if the only purpose for obtaining the sample is
to determine temperature. True or False? - *answers * False
What must be done to the sample container prior to sampling the concrete? - *answers *
Dampen (with water)
What must be done to the concrete surrounding the temperature measuring device after the
device is submerged in the fresh concrete? - *answers * Gently press the concrete around the
temperature-measuring device at the surface of the concrete
How long must the temperature measuring device remain in the freshly mixed concrete? -
*answers * At least 2 minutes but not more than 5 minutes
,ACI Concrete FieldTesting Technician- Grade I
After the temperature of the concrete is read, what is required? - *answers * Reporting of
temperature
The temperature of concrete is reported to the nearest _____ degrees F [_____ C] - *answers *
1 degree F [0.5 C]
According to ASTM C1064, what is one reason to take the temperature of concrete? - *answers
* Verify conformance to a specified requirement for temperature of concrete
A maximum temperature of freshly mixed concrete is specified in ASTM C1064. True of False? -
*answers * False
The sample of concrete used for temperature determination must be rodded 25 times. True or
False? - *answers * False
Sampling by this method is required when tests are to be made to determine _____ with
specification requirements. - *answers * Compliance
This method covers sampling from four types of mixtures which are _____, _____, _____, and
_____. - *answers * Stationary mixers, paving mixers, revolving drum mixers, and open top
mixers
The maximum allowable time between obtaining the first and final portions of a composite
sample is _____ minutes. - *answers * 15
Portions of a composite sample shall be thoroughly remixed bfore beginning tests on the
sample. True of False? - *answers * True
, ACI Concrete FieldTesting Technician- Grade I
The maximum elapsed time allowed between obtaining the final portion of the composite
sample and beginning the tests for slump, temperature, and air content is _____ minutes. -
*answers * 5
The molding of strength test specimens shall begin within _____ minutes after fabricating the
composite sample. - *answers * 15
The concrete sample must be protected from contamination and _____. - *answers * Rapid
evaporation
The minimum size sample for making strength test specimens is _____. - *answers * 28 L (1ft^3)
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 - *answers * 2
The composite sample for a paving mixer must represent a minimum of _____ different portions
of the batch of concrete taken from the pile after discharge. - *answers * 5
When sampling from a revolving drum truck mixer, concrete must be sampled at a minimum of
_____ regularly spaced intervals during discharge of the middle portion of this batch. - *answers
*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? - *answers * False
The composite samples from a truck mixer must be obtained from the _____ portion of the
batch. - *answers * Middle