ACI Certification Exam

2. T/F: When the concrete contains large aggregate, the testing technician should wet-sieve the sample before making unit weight tests for use in yield computations. - Answer-False 4. T/F: Samples smaller than 28L (1 .) are allowed on routine air content, temperature, and slump tests. - Answer-True 7. How do you regulate the rate of discharge of the batch from the revolving truck drum mixer or agitator? - Answer-By the rate of revolution of the drum 10. While the technician is checking the slump of the concrete, there is a decided falling away or shearing off of the concrete from one side of the sample. What should the technician do? - Answer-Disregard the test and retest on another portion of the sample 11. The mold is filled in three equal layers by volume, which makes the first third at _______, and the second third at ________. - Answer-2 5/8, 6 1/8 15. What is the difference allowed by ACI when certifying an individual test using a plastic slump cone vs. a metal slump cone? - Answer-0.5 inches 16. T/F: The sides of the slump mold should be lightly tapped to consolidate the concrete in the mold. - Answer-False 18. T/F: ASTM C 1064 defines the maximum recommended temperature for concrete. - Answer-False 19. The temperature test method must be complete with in _________ after obtaining the sample. - Answer-5 minutes 20. Each temperature-measuring device should be calibrated ________, or whenever there is a question of _________. - Answer-annually, accuracy 23. T/F: After strike off of the measure used to determine density, a small quantity of concrete may be added to correct a deficiency? - Answer-False 26. What is the required shape at the end of the tamping rod? - Answer-rounded to a hemispherical tip 28. How do you find the density of a concrete batch? - Answer-(mass of measure with concrete - mass of measure) / volume of measure