ACI Field Testing Technician Grade 1 Exam Questions and Answers

ACI Field Testing Technician Grade 1 Exam Questions and Answers Obtain Accurate Results - Answer- Why collecting a representative concrete sample is important The 4 types of sampling covered by ASTM C172/C172M-17 - Answer- STATIONARY MIXER, REVOLVING TRUCK/AGITATNG MIXER, PAVING MIXER, and CONTINUOUS MIXER The Elapsed time between obtaining the first and final portions of a composite sample shall not exceed - Answer- 15 minutes Portions of a composite sample shall be thoroughly remixed before beginning testing on a sample - Answer- True The time within which tests for slump, temperature and air content must be started after obtaining the composite sample - Answer- 5 Minutes The time within which the molding of strength specimens needs to begin after obtaining a composite sample - Answer- 15 minutes A concrete sample must be protected from - Answer- Contamination, Evaporation/Rapid Moisture Loss. As well as extreme temperature variations This is the minimum sample size for strength specimens - Answer- 1 cubic foot When sampling from a stationary mixer, the batch must be sampled THIS MANY times from the middle of the batch - Answer- 2 When sampling from a Paving Mixer, the batch must be sampled from THIS MANY portions of the pile - Answer- 5 When sampling from a revolving truck mixer, sample the concrete by collecting THIS MANY or more portions at regularly spaced intervals in the middle of the batch - Answer- 2 Concrete samples from a truck mixer must be - Answer- Obtained before any water or admixtures are added at the jobsite When concrete contains aggregate larger than allowable for a test, you must - Answer- wet screen/sieve the sample of concrete before conducting the test The stem of the thermometer must be submerged by this amount - Answer- 3 inches or 3 times the nominal maximum aggregate size, whichever is greater The thermometer must be capable of accuracy within - Answer- 1 degree Fahrenheit (0.5 degree Celsius)