ACI Concrete Field-Testing Technician – (2025) Exam Questions & Answers

Terms in this set (133) Q1. Start molding specimens for B. False strength tests within 30 minutes after fabricating the composite ASTM C172 -Para (4.1.2) - Start molding. sample. specimens for strength tests within 15 min after fabricating the composite sample. A. True B. False Q2. The maximum allowable time B. False between obtaining the first and last portions of the composite ASTM C172 - Para (4.1)- The elapsed time shall not exceed 15 sample may not exceed 5 min. between obtaining the first and final portions of the minutes. composite sample. A. True B. False Q3. The composite concrete A. True sample must be protected from sun, wind, ASTM C172 - Para (4.1.2) contamination and rapid evaporation. A. True B. False ,Q4. If the concrete contains A. True aggregates larger than those that are ASTM C172- Para (6.1) appropriate for a size of mold or equipment used, the sample should be wet sieved before making the test. A. True B. False Q5. The composite sample should B. False not be remixed before beginning any tests. ASTM C172-Para (4.1.1) -The sample shall be combined and remixed with a shovel the minimum amount necessary to ensure A. True uniformity and compliance with the maximum time limits B. False B. False Q6. Sampling should normally be performed, as the ASTM C172-Para (5). NOTE 2—Sampling should normally concrete is discharged from be performed as the concrete is delivered from the mixer. the mixer. To the conveying vehicle used to transport the A. True concrete to the forms; however, specifications may require B. False other points of sampling, such as the discharge of a concrete pump. Q7. ASTM Method C172 A. True includes sampling from stationary mixers, paving ASTM C172- Para (1.1) mixers, truck mixers, agitators, and non-agitating equipment. A. True B. False Q8. After sampling is D. None of the above completed, start the tests for slump and air content ASTM C172- Para (4.1.2) Start tests for slump, temperature, within: and air content within 5 min after obtaining the final portion of the composite sample. A. 2 ½ minutes B. 10 minutes , C. 15 minutes D. None of the above Q9. In any case, do not obtain A. All the water and admixtures have been added to the concrete. samples until: ASTM C172- Para (5.2.3). In any case do not obtain samples A. All the water and admixtures until after all of the water has been added to the mixer. have been added to the concrete B. 200 revolutions of the drum have been obtained C. ½ of the water has been added D. None of the above