Astm C172-C172M Sampling Freshly Mixed Concrete

Front 1

Sampling by this method is required when tests are to be made to determine _______ with specification requirements

Back 1

compliance

Front 2

This method covers sampling from four types of mixers which are

Back 2

Open top, revolving drum, paving mixer, stationary mixer

Front 3

The maximum allowable time between obtaining the first and final portions of a composite sample is _____ minutes

Back 3

15 minutes

Front 4

Portions of a composite sample shall be thoroughly remixed before beginning tests on the sample. T or F?

Back 4

True

Front 5

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

Back 5

5 minutes

Front 6

The molding of strength test specimens shall begin within ______ minutes after fabricating the composite same

Back 6

15 minutes

Front 7

The concrete sample must be protected from contamination and

Back 7

evaporation, sun and wind

Front 8

the minimum size sample for making strength test specimens is

Back 8

28L or 1ft^3

Front 9

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

Back 9

2

Front 10

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

Back 10

5

Front 11

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 the batch

Back 11

2

Front 12

Concrete samples from a truck mixer must be obtained before any water or admixtures are added to the mixer at the job site. T or F

Back 12

False

Front 13

The composite sample from a truck mixer must be obtained from the _____ portion of the batch.

Back 13

Middle

Front 14

When the concrete contains aggregates larger than that permitted for a particular test method, the sample of concrete must be ____ ______ before making the test

Back 14

Wet sieved