27-02-2013, 09:24 AM
CONCRETE MIX DESIGN
CONCRETE MIX.pdf (Size: 123.59 KB / Downloads: 328)
Scope.
This method covers the procedure for designing concrete mixes and is based on the absolute volumes of
the various components of the mix, i.e.: the absolute volumes of cement (plain, blended or fly ash
modified), aggregate, water and air in one cubic yard of concrete.
Complete Part I of the form. This includes the class of concrete, the water-cement ratio, specified
minimum cement factor, percent air, and the specific gravity (Bulk, Saturated Surface Dry Basis) of each
aggregate.
The specific gravity is determined by tests conducted on samples obtained from project stockpiles. Due
to differences in processing and gradation, there may be n appreciable difference between the specific
gravity of the aggregate submitted to the Laboratory and the specific gravity of the aggregate in the
project stockpiles.
When designing concrete mixes composed of sweetened mixed aggregate, the percentage of each
aggregate may be determined by specification requirements, or the contractor may elect to use certain
aggregate combinations to produce the required gradation.