ACI Concrete Field Testing Technician- Grade I Questions & Answers Solved 100% Correct!!

The sensor of the temperature measuring device shall be submerged a minimum of _____ in. [_____mm] into the freshly mixed concrete. - Answer-3 in. [75 mm] The temperature measuring device shall have a capacity of measuring temperature of freshly mixed concrete to +- _____ degrees F [+- _____ C] throughout a range of _____. - Answer-1 degree F [0.5 C], 30 degrees F to 120 F [0 C to 50 C] The temperature measuring device shall be calibrated _____, or whenever there is a question of _____. - Answer-Annually, accuracy The temperature of concrete may be measured in a wheelbarrow. True or False? - Answer-True The temperature of concrete may be measured in a wall form. True of False - Answer-True A composite sample of concrete is required even if the only purpose for obtaining the sample is to determine temperature. True of False? - Answer-False What must be done to the sample container prior to sampling the concrete? - Answer-Dampen (with water) What must be done to the concrete surrounding the temperature measuring device after the device is submerged in the fresh concrete. - Answer-Gently press the concrete around the temperature measuring device at the surface of the concrete How long must the temperature measuring device remain in the freshly mixed concrete? - Answer-At least 2 minutes but not more than 5 minutes After the temperature of the concrete is read, what is required? - Answer-Reporting of temperatureThe temperature of concrete is reported to the nearest _____ degrees F [_____ C] - Answer-1 degree F [0.5 C] According to ASTM C1064, what is one reason to take the temperature of concrete? - Answer-Verify conformance to a specified requirement for temperature of concrete A maximum temperature of freshly mixed concrete is specified in ASTM C1064. True of False? - AnswerFalse The sample of concrete used for temperature determination must be rodded 25 times. True or False? - Answer-False Sampling by this method is required when tests are to be made to determine _____ with specification requirements. - Answer-Compliance This method covers sampling from four types of mixtures which are _____, _____, _____, and _____. - Answer-Stationary mixers, paving mixers, revolving drum mixers, and open top mixers The maximum allowable time between obtaining the first and final portions of a composite sample is _____ minutes. - Answer-15 Portions of a composite sample shall be thoroughly remixed bfore beginning tests on the sample. True of False? - Answer-True The maximum elapsed time allowed between obtaining the final portion of the composite sample and beginning the tests for slump, temperature, and air content is _____ minutes. - Answer-5 The molding of strength test specimens shall begin within _____ minutes after fabricating the composite sample. - Answer-15 The concrete sample must be protected from contamination and _____. - Answer-Rapid evaporationThe minimum size sample for making strength test specimens is _____. - Answer-28 L (1ft^3) When sampling from a stationary mixer, the batch must be sampled at _____ or more regularly spaced intervals during discharge of the middle portion of the batch - Answer-2 The composite sample for a paving mixer must represent a minimum of _____ different portions of the batch of concrete taken from the pile after discharge. - Answer-5 When sampling from a revolving drum truck mixer, concrete must be sampled at a minimum of _____ regularly spaced intervals during discharge of the middle portion of this batch. - Answer-2 Concrete samples from a truck mixer must be obtained before any water or admixtures are added to the mixer at the job site. True or False? - Answer-False The composite samples from a truck mixer must be obtained from the _____ portion of the batch. - Answer-Middle When the concrete contains aggregate larger than that permitted for a particular test method, the sample of concrete must be _____ _____ before making the test. - Answer-Wet sieved The slump test is applicable to plastic concrete with a maximum size aggregate of _____. - Answer-1.5 in. [37.5 mm] When the concrete contains aggregate larger than allowed for the slump test, the large aggregate must be _____. - Answer-Removed by wet sieving the sample over 1.5 in. [37.5 mm] sieve The mold for making the slump test is in the shape of _____. - Answer-The frustum of a cone The height of the slump mold is _____. - Answer-12 in. [300 mm]The interior surface of the slump mold is allowed to have minor irregularities. True or False? - AnswerFalse For use in the slump test, the end or both ends of the tamping rod must be _____. - Answer-Rounded to a hemispherical tip The sample of concrete for use in making the slump test must be obained in accordance with ASTM Standard _____. - Answer-C172, Standard Practice for Sampling Freshly Mixed Concrete The slump mold should be in a dry condition before beginning the test. True or False? - Answer-False The surface on which the slump mold will be placed must be _____. - Answer-Flat, level, moist, nonabsorbent, and free of vibration The slump mold is filled in _____ layers. - Answer-3 Each layer should fill approximately _____ the volume of the mold. - Answer-One-third