CCIL Concrete UPDATED ACTUAL Exam
Questions and CORRECT Answers
Procedure for sampling plastic concrete includes - CORRECT ANSWER - Every
precaution that will assist in obtaining samples that are truly representative of the nature and
conditions of the concrete
When sampling from a truck agitator or truck mixer, - CORRECT ANSWER - The sample
shall be taken between the 10% and 90% points of the discharge
Grab Sampling - CORRECT ANSWER - The operation of securing at one point of the
discharge the required volume of representative material in as short a period of time as possible.
Sampling for uniformity of mixed concrete includes: - CORRECT ANSWER - Obtaining
three grab samples of concrete for comparative purposes while the mixer is being emptied and
keep the samples separate to represent the designated portions in the batch rather than combined
to form a composite sample.
When 100 mm x 200 mm cylinders are to be cast: - CORRECT ANSWER - A minimum
20 L sample shall be obtained.
When 150 mm x 300 mm cylinders are to be cast: - CORRECT ANSWER - A minimum
30 L sample shall be obtained.
When 150 mm x 150 mm x 535 mm cylinders are to be cast: - CORRECT ANSWER -A
minimum 55 L sample shall be obtained.
For more than three cylinders or beams, the minimum volume shall be increased - CORRECT
ANSWER - By a value equal to the volume of the extra specimens, plus 10%.
Sampling shall by performed - CORRECT ANSWER - By passing a receptacle completely
through the discharge stream or by completely diverting the discharge into a sample container.
, The sample shall be obtained, transported, and remixed - CORRECT ANSWER - Within
10 minutes.
The sample shall be protected - CORRECT ANSWER - From sun, wind, and other sources
of rapid evaporation and from contamination.
When the concrete contains aggregate larger than that appropriate for the size of the moulds or
equipment to be used, - CORRECT ANSWER - the sample shall be wet sieved prior to
testing. For all density tests, an unsieved sample shall be used.
Do not use cardboard moulds: - CORRECT ANSWER - When the specified concrete
strength is greater than 35 MPa.
Rectangular moulds: - CORRECT ANSWER - Should be at least 50 mm longer than the
length of the span. Moulds shall be watertight and made of rigid, nonabsorbent material.
Tamping rod for 100 x 200 mm cylinders - CORRECT ANSWER - Straight steel 10 +- 1
mm in diameter and between 450 and 600 mm in length, having at least one end rounded to a
hemispherical tip.
Tamping rod for cylinders 150 mm in diameter or greater - CORRECT ANSWER -
Straight steel 16 +- 1 mm in diameter and between 450 and 600 mm in length, having at least one
end rounded to a hemispherical tip.
The frequency of vibration of an internal vibrator shall be a minimum of - CORRECT
ANSWER - 120 Hz
The outside diameter of the internal vibrator shall be - CORRECT ANSWER - 20 to 40
mm
Questions and CORRECT Answers
Procedure for sampling plastic concrete includes - CORRECT ANSWER - Every
precaution that will assist in obtaining samples that are truly representative of the nature and
conditions of the concrete
When sampling from a truck agitator or truck mixer, - CORRECT ANSWER - The sample
shall be taken between the 10% and 90% points of the discharge
Grab Sampling - CORRECT ANSWER - The operation of securing at one point of the
discharge the required volume of representative material in as short a period of time as possible.
Sampling for uniformity of mixed concrete includes: - CORRECT ANSWER - Obtaining
three grab samples of concrete for comparative purposes while the mixer is being emptied and
keep the samples separate to represent the designated portions in the batch rather than combined
to form a composite sample.
When 100 mm x 200 mm cylinders are to be cast: - CORRECT ANSWER - A minimum
20 L sample shall be obtained.
When 150 mm x 300 mm cylinders are to be cast: - CORRECT ANSWER - A minimum
30 L sample shall be obtained.
When 150 mm x 150 mm x 535 mm cylinders are to be cast: - CORRECT ANSWER -A
minimum 55 L sample shall be obtained.
For more than three cylinders or beams, the minimum volume shall be increased - CORRECT
ANSWER - By a value equal to the volume of the extra specimens, plus 10%.
Sampling shall by performed - CORRECT ANSWER - By passing a receptacle completely
through the discharge stream or by completely diverting the discharge into a sample container.
, The sample shall be obtained, transported, and remixed - CORRECT ANSWER - Within
10 minutes.
The sample shall be protected - CORRECT ANSWER - From sun, wind, and other sources
of rapid evaporation and from contamination.
When the concrete contains aggregate larger than that appropriate for the size of the moulds or
equipment to be used, - CORRECT ANSWER - the sample shall be wet sieved prior to
testing. For all density tests, an unsieved sample shall be used.
Do not use cardboard moulds: - CORRECT ANSWER - When the specified concrete
strength is greater than 35 MPa.
Rectangular moulds: - CORRECT ANSWER - Should be at least 50 mm longer than the
length of the span. Moulds shall be watertight and made of rigid, nonabsorbent material.
Tamping rod for 100 x 200 mm cylinders - CORRECT ANSWER - Straight steel 10 +- 1
mm in diameter and between 450 and 600 mm in length, having at least one end rounded to a
hemispherical tip.
Tamping rod for cylinders 150 mm in diameter or greater - CORRECT ANSWER -
Straight steel 16 +- 1 mm in diameter and between 450 and 600 mm in length, having at least one
end rounded to a hemispherical tip.
The frequency of vibration of an internal vibrator shall be a minimum of - CORRECT
ANSWER - 120 Hz
The outside diameter of the internal vibrator shall be - CORRECT ANSWER - 20 to 40
mm
