Making And Curing Concrete Compression And Flexural Test Specimens

Question 1

CSA A23.2–3 C specifies the procedure for _______, and _______, compression test cylinders and flexural test beams from samples of plastic concrete

Answer 1

Making / curing

Question 2

The tamping rod must be a round straight steel rod with a diameter of _______, millimetres for the standard 100 x 200 mm cylinders

Answer 2

10 +- 1

Question 3

Used for moulding strength test specimen shall be obtained in accordance with what CSA A23.2 test procedure

Answer 3

1C

Question 4

Cylinder moulds, of 100 mm diameter can be used for concrete containing aggregate with particles up to _______, millimetres in size

Answer 4

28 mm (closest sieve size to 1/3 of 100 mm]

Question 5

The moulding strength of test specimens must be completed within _______, minutes after sampling, including transport and mixing

Answer 5

20 minutes

Question 6

After moulding test specimens, you should wait two hours before moving them to the nearby location of initial storage

Answer 6

False

Question 7

Concrete with a specified slump of 100 mm the test specimens must be consolidated by what method

Answer 7

Rodding

Question 8

If vibration is the selected method of consolidation a standard 100 mm by 200 mm cylinder must be filled in _______, equal layers.

Answer 8

2

Question 9

When rotting 100 x 200 mm cylinder, each layer must be rodded _______, times with a rod of _______, millimetre diameter.

Answer 9

20 / 10 mm

Question 10

When broaden the second and final layer of a cylinder, the camping rod should penetrate the previous layer by about _______,

Answer 10

25 mm

Question 11

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

Answer 11

8 (40%)

Question 12

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

Answer 12

Three

Question 13

When consolidating a flexural strength test specimen by rodding each layer shall be rodded evenly over its area once for every _______, of area

Answer 13

10 cm2

Question 14

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

Answer 14

150 mm

Question 15

If no slump concrete is to be tested, which consolidation technique is required during moulding.

Answer 15

Special means of consolidation (vibration)

Question 16

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.

Answer 16

15 / 25

Question 17

What is the required time for demolding of strength specimens made in the field?

Answer 17

28+-8 hours

Question 18

The standard demolding time may be extended to a maximum of _______, hours for concrete of less than _______, MPA

Answer 18

76 / 35

Question 19

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.

Answer 19

Moist / 23+-2

Question 20

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.

Answer 20

False

Question 21

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.

Answer 21

True

Question 22

Specimens for determining when concrete is put into service must be stored in _______, at _______, for _______, hours immediately prior to testing

Answer 22

Lime Saturated Water / 23+-2 / 24+-4

Question 23

During transportation test specimens must be protected from damage from _______, or _______,

Answer 23

Shocks / Exposure to Adverse Conditions

Question 24

The test report must include the _______, and _______, ambient air temperatures measured during the initial curing period.

Answer 24

Minimum / maximum

Question 25

For self-controlled concrete compression and flexural test specimens shall be filled _______, in _______, lift to slightly _______, the top of the mould

Answer 25

Continuously / one / overfill

Question 26

For self consolidating concrete, the outer sides of the mould shall be tapped lightly _______, times with the mallet until _______,

Answer 26

10 or more / no large air bubbles & voids are closed