ACI Aggregate Testing Technician - Level 1 - Section 7

ACI Aggregate Testing Technician - Level 1 - Section 7 For most purposes, this test method measures the moisture in a test sample more reliably than the test sample ______ . Can be made to represent the aggregate supply A ventilated controlled-temperature oven should be used for the test when the aggregate is _____ by heat or when a more _____ measurement is required. Altered, refined· (or their equivalents) It takes longer for moisture to travel from the interior of a large particle of coarse aggregate to its exterior surface than from the interior of a small particle to its surface. True or False? True Quick-drying methods provide accurate results when used on large particles. True or False or Unknown? Unknown; the user should determine by trial If rapid drying methods provide sufficient accuracy for their intended use The samples may be dried on a hot plate, with an electric ____ , in a ventilated ____ , or in a ventilated _____ . Heat lamp, oven, microwave oven Which of the following are requirements for an acceptable container: a) It should always be metallic b) It should be large enough to eliminate spilling c) It should be unaffected by heat d) It should be twice as deep as the sample b) and c) An ordinary frying pan should never be used with a hot plate because of heat transfer problems. True or False? False; there are no heat transfer problems The mass of the test sample should be determined before and after the test to the nearest ______ . 0.1% ______ may cause particles to explode. Very rapid heating To speed up the drying time and to avoid overheating in certain areas, ____ the sample when using a hot plate or heat lamp. Stir The presence of particular ____ in aggregates may cause ____ and ____ in microwave ovens. Minerals, overheating, explosions When further heating causes, or would cause, less than 0.1 % added ____ , the sample may be considered thoroughly ______ . loss in mass, dry