Section 1 Flashcards
Collecting a representative sample of concrete to be tested is an important as executing the test methods to obtain,_____
accurate results
This practice covers sampling from four types of equipment which are…..
stationary mixer, paving mixers, revolving truck mixers, continuous mixers
The elapsed time between obtaining the first and final portions of a composite sample shall not exceed _______
15 min
true or false: Portions of a composite sample shall be thourouly remixed before beginning tests on sample
true
start test for slump, temp, and air content within _______ after obtaining the final portion of the composite sample.
5 min
start molding specimens for strength tests within ________ after fabricating the composite sample
15 min
concrete sample must be protected from contamination and __________
evaporation
the minimum size sample for making strength specimens is
1 cf
when sampling from a stationary mixer the batch must be sampled at _____ or more regular spaced intervals during discharge of the middle portion of the batch
2
when sampling from a paving mixer, obtain samples from at least ______ different portions of the pile and combine them into one composite sample for test purposes
five
when sampling from a revolving truck mixer sample the concrete by collecting _____ or more portions take at regularly spaced intervals during discharge of the middle portion of the batch
two
true or false : concrete samples from a truck mixer must be obtained before any water or admixtures are added to the mixer at the job site
false
when concrete contains aggregate larger than that permitted for a particular test method the sample of concrete must be ___________ before making the test
wet screened
