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CCIL EXAM QUESTIONS WITH COMPLETE
SOLUTION
1. Sampling from a mixer/truck agitator- Where is sample taken?: Between 10% and
90% (Not when testing with Super P)
2. How is a sample taken when sampling plastic concrete?: Either pass a receptacle
completely through a discharge stream OR divert a discharge stream completely into a sampling container.
3. How many grab samples are needed when testing for uniformity of sam-ples?:
4. What size sample is needed when casting 3 100mm x 200mm cylinders?: -
Minimum 20L
5. What size sample is needed when casting 150mm x 300mm cylinders?: Mini-mum
30L
6. What size sample is needed when casting 150mm x 150mm x 535mm
beams?: Minimum 55L
7. How much extra sample is needed when more than 3 cylinders/specimens are to be
cast?: Volume of the cylinders/specimens plus 10% extra
8. How much time is allowed for obtaining, transporting and remixing the
sample?: 10 minutes
9. A sample contains aggregate larger than that appropriate for the size of the
moulds or equipment.: It must be wet-sieved prior to testing
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10. Information required on reports: Conc mix no, Sample source, Batch time/date, Sample
time/date, Project site, Sample location if ditterent, Location of conc in structure, Technician name, Lab name/address, Signature of test report reviewer, Any deviation from test procedures
11. Air Content: The volume of air voids of plastic concrete, exclusive of pore space in aggregate particles,
determined through observations of the change of air volume in concrete with a change in pressure.
12. Slump: A measure of consistency of freshly mixed hydraulic cement concrete, equal to the subsidence,
measured to the next 5mm, of the moulded substance immediately after the removal of the slump cone
13. Slump Flow: The horizontal spread of concrete immediately upon removal of the slump cone as a measure of
the unconfined fluidity of concrete giving a relative degree of indication of the degree to which concrete can travel
14. How many water-to-cementing materials ratios are needed for concrete
trial mixes?: 3
15. What temperature is considered stable before mixing concrete?: 23 C +/- 2 C
16. Where should cementing materials be stored?: In a dry place, in moisture-proof contain-
ers
17. What sieve must cementing materials be passed through before use to
reject lumps?: 1.25mm or finer
18. Surface moisture in fine and coarse aggregate should be obtained using
samples of what size?: 500g-1000g
19. How much time is spent mixing concrete?: Mix 3 minutes, rest 3 minutes, mix 2 minutes
20. Which sample can be re-used for casting cylinders?: Slump or slump flow, NOT air. Must
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33. Water Tank Cleaning: When water contains 3g/L Ca at intervals not to exceed 24 months.
34. Water Tank Room: 95% or greater humidity, 23 +/- 2 degrees C, temperature readings twice daily 5 days a
week within 0.5 degrees C accuracy.
35. Temperature measuring: Devices must be able to measure temperatures between 0 and 50 degrees
C, accurate to 0.5 degrees C.
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36. Moisture Room: Temperature must be read every 15 mins by a recorder- Must be accurate to 1 degree C.
37. Verify temperature recorders: Every 6 months or whenever there is a question of accuracy
38. Reference Temperature Measuring Device: Available for calibration of other devices, MUST
be accurate to +/- 0.2 degrees C. Must have certificate or document available for view.
39. Specimens must be moulded when?: 20 minutes after sample time, including transport and
remixing.
40. Specimen/Aggregate Size: Diameter of a cylindrical specimen, or cross-sectional dimension of a
beam shall be at least 3 times the size of the coarse aggregate used in the concrete.
41. Handpicking: Can be used to remove over-sized aggregate before casting cylinders.
42. Cylinder Moulding Location: Mould closest to where cylinders will initially cure. Must stay in cure
location for 28 +/- 8 hours.
43. Consolidating Test Specimens: Rodding used with slump greater than 40, vibration used with
slump equal or less than 40.
44. Placing Concrete In Moulds: 2 or 3 lifts or layers.
45. Finishing Mould Surface: No depressions larger than 3mm if specified strength is less than 35
MPa, none larger than 1mm at 35 MPa or greater.
46. Finishing Beams: Wood float
47. Rodding - 100mm cylinder: 20 strokes/lift
48. Rodding - 150mm cylinder: 25 strokes/lift
7 / 25mm into layer below. Slightly overfill top layer.
62. Flexural Specimens - Internal Vibration: Intervals not exceeding 150mm along the centreline
of the long dimension of the specimen. Wider than 150mm, use alternating insertions along 2 lines.
63. How long do flexural test specimens initially cure before demoulding?: 48 +/- 4
hrs. Store in lime water (23 +/- 2 degrees C) for 24 +/- 4 hrs before testing.
64. Tampering Rod Dimensions for Air Content Test: 16mm +/- 1mm Diameter, between
450mm and 600mm length. One end must have a hemispherical tip.
65. Measuring Bowl: Suflciently rigid to limit expansion to 0.1% of scale reading at operating pressure. 7L
bowl maximum aggregate size of 40mm, 15L bowl maximum aggregate size of 56mm.
66. Air Guage Dial: Permits direct reading to a minimum of 0.2% for air volumes in the usual range of 0-8%.
67. Calibration Cylinder: Volume in the range of 1-6% of the volume of the base container.
68. Air Meter Readings: Are to the nearest 0.1%.
69. How long do you have to conduct your air test from collecting your sam-
ple?: 10 minutes.
70. Air Meter Rodding: 15L - 25 strokes. Greater than 15L - 50 strokes.
71. Slump on Mixtures with aggregate larger than 40mm: Sample is sieved and
slump test is conducted with material that passed through a 40mm sieve. Not applicable to non-plastic concrete.
72. Slump Cone Specs: Minimum 1.5mm thickness, Base 200 +/- 3mm diameter, Top 100 +/- 3mm Diameter,
Height 300 +/- 3mm. Base and top parallel to each other and at right angles to axis of cone.
73. Slump Board: Minimum 19mm thickness.
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74. Slump Measuring: Tape minimum 300mm length and reading in 1 mm gradations.
75. Slump Test: Done in 2 minutes or less. If 2 operators testing, 4 minutes or less.
76. When measuring slump read to the nearest how many mm?: 5
77. Bearing Surface Minimum Dimension: At least 3% greater than the specimen
78. Bearing Surfaces Should Not Depart from the plane...: More than 0.025mm.
New blocks are manufactured at half that.
79. Bottom Bearing Block: At least 25mm thick when new, 22.5mm thick after resurfacing. Must be 3%
greater than specimen,
80. Bearing Face Diameter 13mm greater than specimen?: Concentric circles no more
than 0.8mm deep and not more than 1.2mm wide should be inscribed to properly centre cylinder.
81. Upper Bearing Block: The centre of the sphere should coincide with the surface of the bearing face with
a tolerance of +/-5% of the radius of the sphere.
82. Stress Level Limit on Ball and Socket: 85MPa for 150mm diameter cylinders
83. How do you keep the curved surface of the socket lubricated?: Petroleum Based
Oil
84. What happens if the radius of the sphere is less than the radius of the
cylinder?: The thickness of the bearing face should not be less than the ditterence between the radius of the sphere and the radius of the diagram.
85. Movable Portion of Bearing Block: Must be able to rotate freely and tilt 4 degrees in any direction.
86. Capping Recess/Mould: Depth 5-12mm and shall be 10-25mm larger than diameter of specimen.
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99. Average specimen density: Should be 98-102% of the mix design plastic concrete density specified
by the supplier.
100. Freshly Mixed Concrete Temperature: Sample container made large enough to ensure 75mm
of concrete is in all directions around the temperature sensor or at least 3 times the nominal maximum size of the aggregate, Must measure from 0 to 50 degrees C and be within 0.5 degrees C accuracy. Calibration must be within 0.2 degrees C.
101. How long do you have to take a temperature reading of your sample after
you have collected it?: 5 minutes.
102. Slump Flow Sample: Anything that would be retained on a 28mm sieve must be sieved ott first before
testing
103. Slump Flow Test: Fill cone to slightly above, don't rod, strike ott, raise immediately 225mm +/- 75mm
above surface in approximately 3 +/- 1 seconds. Allow maximum spread or 2 minutes to pass. This test should take 3 minutes. Report to the nearest 10mm.
