Making And Curing Concrete Compression And Flexural Test Specimens Flashcards
CSA A23.2–3 C specifies the procedure for _______, and _______, compression test cylinders and flexural test beams from samples of plastic concrete
Making / curing
The tamping rod must be a round straight steel rod with a diameter of _______, millimetres for the standard 100 x 200 mm cylinders
10 +- 1
Used for moulding strength test specimen shall be obtained in accordance with what CSA A23.2 test procedure
1C
Cylinder moulds, of 100 mm diameter can be used for concrete containing aggregate with particles up to _______, millimetres in size
28 mm (closest sieve size to 1/3 of 100 mm]
The moulding strength of test specimens must be completed within _______, minutes after sampling, including transport and mixing
20 minutes
After moulding test specimens, you should wait two hours before moving them to the nearby location of initial storage
False
Concrete with a specified slump of 100 mm the test specimens must be consolidated by what method
Rodding
If vibration is the selected method of consolidation a standard 100 mm by 200 mm cylinder must be filled in _______, equal layers.
2
When rotting 100 x 200 mm cylinder, each layer must be rodded _______, times with a rod of _______, millimetre diameter.
20 / 10 mm
When broaden the second and final layer of a cylinder, the camping rod should penetrate the previous layer by about _______,
25 mm
For a flowing Super plasticized concrete mix having a slump greater than 180 mm cylinders of 100 mm diameter shall be rodded _______, times per layer
8 (40%)
When using an internal vibrator to consolidate 150 mm x 300 mm compressive strength test specimen, the vibrator must be inserted at _______, different points for each layer
Three
When consolidating a flexural strength test specimen by rodding each layer shall be rodded evenly over its area once for every _______, of area
10 cm2
When vibrating a flexural strength test specimen using internal vibration, the vibrator should’ve be inserted at intervals not exceeding _______, along the centre line of the beam
150 mm
If no slump concrete is to be tested, which consolidation technique is required during moulding.
Special means of consolidation (vibration)
After moulding strength specimens for field, curing, the test specimen shall be stored in a controlled environment that maintains the temperature in the range of _______, to _______, during initial curing.
15 / 25
What is the required time for demolding of strength specimens made in the field?
28+-8 hours
The standard demolding time may be extended to a maximum of _______, hours for concrete of less than _______, MPA
76 / 35
Upon completion of the initial curing period, compressive strength test specimens used as the basis of acceptance shall be stored in a _______, condition at _______, until the time of test.
Moist / 23+-2
Cylinders which have been subjected only to field cure conditions prior to testing may be used to assess the quality of the concrete as delivered.
False
Only cylinders or flexural beams, which have been kept on site under temperature and moisture conditions similar to that received by in-place concrete. May be used to assess for removal in service or post tensioning times.
True
Specimens for determining when concrete is put into service must be stored in _______, at _______, for _______, hours immediately prior to testing
Lime Saturated Water / 23+-2 / 24+-4
During transportation test specimens must be protected from damage from _______, or _______,
Shocks / Exposure to Adverse Conditions
The test report must include the _______, and _______, ambient air temperatures measured during the initial curing period.
Minimum / maximum
For self-controlled concrete compression and flexural test specimens shall be filled _______, in _______, lift to slightly _______, the top of the mould
Continuously / one / overfill
For self consolidating concrete, the outer sides of the mould shall be tapped lightly _______, times with the mallet until _______,
10 or more / no large air bubbles & voids are closed
