ACI Certification Exam Questions with Complete Solutions | Verified & Updated 2024

ACI Certification Exam Questions with Complete Solutions | Verified & Updated 2024 ASTM C172 covers sampling from stationary, paving and truck mixers, and from agitating and non-agitating equipment used to transport central-mixed concrete. - Answer ️️ -True When the concrete contains large aggregate, the testing technician should wet-sieve the sample before making unit weight tests for use in yield computations. - Answer ️️ -False Samples should be taken before 10% or after 90% of the batch has been discharged. - Answer ️️ -False Samples smaller than 28L (1 .) are allowed on routine air content, temperature, and slump tests. - Answer ️️ -True Tests for slump and air content must be started within ____________ after obtaining the final portion of the composite sample. - Answer ️️ -5 Minutes Start molding strength test specimens within ________ after fabricating the composite sample. - Answer ️️ -15 Minutes How do you regulate the rate of discharge of the batch from the revolving truck drum mixer or agitator? - Answer ️️ -By the rate of revolution of the drum The mold is in the shape of a ___________________. - Answer ️️ -Frustrum of a Cone The top diameter of a slump cone is ______ and the diameter at the base is ________. - Answer ️️ -4", 8" While the technician is checking the slump of the concrete, there is a decided falling away or shearing off of the concrete from one side of the sample. What should the technician do? - Answer ️️ -Disregard the test and retest on another portion of the sample The mold is filled in three equal layers by volume, which makes the first third at _______, and the second third at ________. - Answer ️️ -2 5/8, 6 1/8 The maximum size of aggregate allowed for ASTM C143 is _________. - Answer ️️ -1 ½" When rodding the second and third layers the rod should penetrate through the layer and into the previous layer________. - Answer ️️ -1" The slump of the concrete was determined to be 4 5/16" what should be recorded as the slump? - Answer ️️ -4 1/4