Grade I
According to ASTM C1064, what is one reason to take the temperature of concrete? -
CORRECT ANSWER-to verify conformance to a specific requirement.
A max. temp. of freshly mixed concrete is specified in ASTM C1064. T/F - CORRECT
ANSWER-False
The sample of concrete used for temperature determination must be rodded 25 times. -
CORRECT ANSWER-False
Sampling by this method covers procedures or obtaining representative samples, on
which test are to be performed to determined __ with quality requirements of the
specifications under which the concrete is furnished. - CORRECT ANSWER-
Compliance
This method covers sampling from four types of mixers, which are __, __, __, and __. -
CORRECT ANSWER-Stationary mixers / Paving mixers / revolving drum mixers / open
top mixers
The elapsed time between obtaining the first and final portions of a composite sample
shall not exceed __ min. - CORRECT ANSWER-15 min.
Portions of a composite sample shall be thoroughly mixed before beginning test on the
sample. T/F - CORRECT ANSWER-True
Start tests for slump, temp, and air content within __ min. after obtaining the final portion
of the composite sample. - CORRECT ANSWER-5 min.
The end of the temperature sensing portion of the temperature measuring device is
submerged a minimum of __mm [__in.] into the freshly mixed concrete. - CORRECT
ANSWER-77mm /3in.
The temperature measuring device shall be capable of accurately measuring the
temperature of freshly mixed concrete to +- __C [+__F] throught a range of __. -
CORRECT ANSWER-0.5 C / +-1F / 0-50 Decrees C
The temp. measuring device shall be verified __, or whenever there is a question of __.
- CORRECT ANSWER-Annually / accuracy
, The temp of concrete may be measured in a wheelbarrow? T/F - CORRECT ANSWER-
True
The temp. of concrete may be measured in a wall form. T/F - CORRECT ANSWER-
True
A composite sample of concrete is required even if the only purpose for obtaining the
sample is to determine temp. T/F - CORRECT ANSWER-False
What must be done to the sample container prior to sampling the concrete - CORRECT
ANSWER-It must be dampened with water
What must be done to the concrete surrounding the temp measuring device after the
device is submerged in the fresh concrete? - CORRECT ANSWER-Gently press the
concrete at the surface around the measuring device.
How long must the temperature measuring device remain in the freshly mixed concrete?
- CORRECT ANSWER-At least 2 min., no longer than 5 min.
After the temperature of the concrete is read, what is then required? - CORRECT
ANSWER-Reporting of temp.
The temp. of concrete is reported to the nearest __. - CORRECT ANSWER-1 degree F
start molding specimens fr strength tests within __ after fabrication the composite
sample. - CORRECT ANSWER-15 min.
The concrete sample must be protected from contamination and __. - CORRECT
ANSWER-Rapid evaporation
The maximum size sample for making strength test specimens is __ ft cubed -
CORRECT ANSWER-1 foot cubed.
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. -
CORRECT 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 - CORRECT
ANSWER-5
When sampling from a REVOLVING DRUM TRUCK mixer, sample the concrete by
collecting __ or more portions taken at regularly spaced intervals during discharge of
the middle portion of the batch. - CORRECT ANSWER-2