ACI Concrete Field Testing Technician-
Grade I
1. The sensor of the temperature measuring device shall be submerged a minimum
of 3 in. [75 mm] into the freshly mixed concrete.
2. The temperature measuring device shall have a capacity of measuring
temperature of freshly mixed concrete to ±1°F [±0.5°C] throughout a range
of 30°F to 120°F [0°C to 50°C].
3. The temperature measuring device shall be calibrated annually, or whenever
there is a question of accuracy.
4. The temperature of concrete may be measured in a wheelbarrow. True.
5. The temperature of concrete may be measured in a wall form. True.
6. A composite sample of concrete is required even if the only purpose for
obtaining the sample is to determine temperature. False.
7. What must be done to the sample container prior to sampling the
concrete? Dampen (with water).
8. What must be done to the concrete surrounding the temperature measuring
device after the device is submerged in the fresh concrete? Gently press the
concrete around the temperature measuring device at the surface of the
concrete.
9. How long must the temperature measuring device remain in the freshly mixed
concrete? At least 2 minutes but not more than 5 minutes.
10. After the temperature of the concrete is read, what is required? Reporting of
temperature.
11. The temperature of concrete is reported to the nearest 1°F [0.5°C].
12. According to ASTM C1064, what is one reason to take the temperature of
concrete? Verify conformance to a specified requirement for temperature of
concrete.
, 13. A maximum temperature of freshly mixed concrete is specified in ASTM
C1064. False.
Sampling Fresh Concrete (ASTM C172)
14. The sample of concrete used for temperature determination must be rodded 25
times. False.
15. Sampling by this method is required when tests are to be made to
determine compliance with specification requirements.
16. This method covers sampling from four types of mixtures: stationary mixers,
paving mixers, revolving drum mixers, and open-top mixers.
17. The maximum allowable time between obtaining the first and final portions of a
composite sample is 15 minutes.
18. Portions of a composite sample shall be thoroughly remixed before beginning
tests on the sample. True.
19. The maximum elapsed time allowed between obtaining the final portion of the
composite sample and beginning the tests for slump, temperature, and air
content is 5 minutes.
20. The molding of strength test specimens shall begin within 15 minutes after
fabricating the composite sample.
21. The concrete sample must be protected from contamination and rapid
evaporation.
22. The minimum size sample for making strength test specimens is 28 L (1 ft³).
23. When sampling from a stationary mixer, the batch must be sampled at 2 or
more regularly spaced intervals during discharge of the middle portion of the
batch.
24. The composite sample for a paving mixer must represent a minimum
of 5 different portions of the batch of concrete taken from the pile after
discharge.
Grade I
1. The sensor of the temperature measuring device shall be submerged a minimum
of 3 in. [75 mm] into the freshly mixed concrete.
2. The temperature measuring device shall have a capacity of measuring
temperature of freshly mixed concrete to ±1°F [±0.5°C] throughout a range
of 30°F to 120°F [0°C to 50°C].
3. The temperature measuring device shall be calibrated annually, or whenever
there is a question of accuracy.
4. The temperature of concrete may be measured in a wheelbarrow. True.
5. The temperature of concrete may be measured in a wall form. True.
6. A composite sample of concrete is required even if the only purpose for
obtaining the sample is to determine temperature. False.
7. What must be done to the sample container prior to sampling the
concrete? Dampen (with water).
8. What must be done to the concrete surrounding the temperature measuring
device after the device is submerged in the fresh concrete? Gently press the
concrete around the temperature measuring device at the surface of the
concrete.
9. How long must the temperature measuring device remain in the freshly mixed
concrete? At least 2 minutes but not more than 5 minutes.
10. After the temperature of the concrete is read, what is required? Reporting of
temperature.
11. The temperature of concrete is reported to the nearest 1°F [0.5°C].
12. According to ASTM C1064, what is one reason to take the temperature of
concrete? Verify conformance to a specified requirement for temperature of
concrete.
, 13. A maximum temperature of freshly mixed concrete is specified in ASTM
C1064. False.
Sampling Fresh Concrete (ASTM C172)
14. The sample of concrete used for temperature determination must be rodded 25
times. False.
15. Sampling by this method is required when tests are to be made to
determine compliance with specification requirements.
16. This method covers sampling from four types of mixtures: stationary mixers,
paving mixers, revolving drum mixers, and open-top mixers.
17. The maximum allowable time between obtaining the first and final portions of a
composite sample is 15 minutes.
18. Portions of a composite sample shall be thoroughly remixed before beginning
tests on the sample. True.
19. The maximum elapsed time allowed between obtaining the final portion of the
composite sample and beginning the tests for slump, temperature, and air
content is 5 minutes.
20. The molding of strength test specimens shall begin within 15 minutes after
fabricating the composite sample.
21. The concrete sample must be protected from contamination and rapid
evaporation.
22. The minimum size sample for making strength test specimens is 28 L (1 ft³).
23. When sampling from a stationary mixer, the batch must be sampled at 2 or
more regularly spaced intervals during discharge of the middle portion of the
batch.
24. The composite sample for a paving mixer must represent a minimum
of 5 different portions of the batch of concrete taken from the pile after
discharge.
