Civil Engineering Reference
In-Depth Information
Concrete production facility has field strength
test records for the specified class of concrete
or within 7 MPa (1000 psi) of the specified class.
No
Yes
≥
30 consecutive
tests
Two groups of consecutive
tests (total
15 to 29 consecutive
tests
≥
30)
Yes
No
Yes
No
Yes
No
(No data
for S)
Calculate and increase
using Table 9-10
Calculate S
Calculate average S
Required average strength
from Eq. (9-1) or (9-2) or (9-3)
Required average strength
from Table 9-11
Field record of at least ten consecutive
test results using similar materials and
under similar conditions is available
or
No
Make trial mixtures using at least three different
w/cm ratios or cementing materials contents
Yes
Results represent
one mixture
No
Results represent two
or more mixtures
Plot average strength versus
proportions and interpolate for
required average strength
Yes
Average
≥
required
average
Plot average strength versus
proportions and interpolate for
required average strength
No
Yes
Submit for approval
Fig. 9-10. Flowchart for selection and documentation of concrete proportions.
