ACI Test 84 Questions with Complete Solutions Graded A+!!The total time allowed between obtaining the first and final portions of a composite sample is - Correct Answer 15 minutes When it is necessary to wet sieve the concrete sample, wet sieving should be performed after the individual samples are remixed into a composite sample (T or F) - Correct Answer F Tests for slump, temperature, and air content must begin within ______ minutes after obtaining the composite sample - Correct Answer 5 minutes Begin molding test specimens within ______ minutes after obtaining the composite sample - Correct Answer 15 minutes The concrete samples should be protected from - Correct Answer the sun, wind, and other sources of rapid evaporation, from contamination When test specimens are to be molded, the minimum size of sample obtained is - Correct Answer 28 L (1 ft^3) The primary objective of the sampling process is to obtain a representative sample (T or
- - Correct Answer T
- x NMS 1 / 2
When sampling from a revolving drum truck mixer collect concrete from ______ portions of the batch - Correct Answer 2 or more Wet sieving is performed - Correct Answer when the concrete contains aggregates larger than appropriate for a test When sampling from a paving mixer it is not acceptable to place 3 small containers on the sub grade in order to obtain the required samples of concrete (T or F) - Correct Answer F TEMPERATURE - Correct Answer it may require up to ___ min before the temp stabilizes when the NMS of the coarse agg is greater than ___ - Correct Answer 20min., 3in.The container for the concrete shall be large enough to provide at least ___ inches, or _____ of coarse agg, of concrete in all directions around the TMD - Correct Answer 3in.,
The temperature measuring device shall have the capability of measuring the temperature of the freshly mixed concrete to ± ______ oF accuracy and have a range of ______ to ______ oF. - Correct Answer 1,30to120 A composite sample of concrete is not required even if the only purpose for obtaining the sample is to determine temperature. T or F - Correct Answer T The Temperature Measuring Device used for determining concrete temperature must be calibrated ______ or whenever there is a question of accuracy. - Correct Answer annually The temperature of freshly mixed concrete can be measured in - Correct Answer all of the above Submerge the sensing portion of the thermometer at least ______ inches into the concrete - Correct Answer 3 Gently press concrete around the thermometer such that the_______ does not affect the reading. - Correct Answer ambient air temp The thermometer must remain in the concrete during the measurement for a minimum of ______ minutes. In addition, the temperature measurement must be completed within _______ minutes after obtaining the sample. - Correct Answer 2, 5 The temperature of freshly mixed concrete is measured and recorded to the nearest _____ - Correct Answer 1 degree SLUMP TEST - Correct Answer ****The slump test does not provide an indication of the water content of a concrete mixture. - Correct Answer F A slump mold can be fabricated from both plastic and metal. - Correct Answer T ****The length of the tamping for the slump test shall be approximately - Correct Answer The slump test is applicable to concrete having a coarse aggregate up to _______ inch in size. - Correct Answer 1.5 inches The height of the slump cone is - Correct Answer 12 in
- The exterior of the slump cone is tapped 10 to 15 times after rodding each layer. -
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Correct Answer F The slump mold is filled with three layers of concrete - Correct Answer by volume