ACI 211.1

The standard practice for selecting proportions for normal, heavyweight and mass concrete: a procedure for arriving at a starting mix from the strength, workability and exposure the concrete has to deliver. It is a PRACTICE and not a code.

It recommends a way of arriving at proportions; it does not require them, and a mix produced by following it is a candidate rather than a compliant design. Its method is absolute volume.

Every ingredient contributes the volume of its own solid — mass divided by specific gravity — and those volumes plus the air must come to the unit volume of concrete, which is why the measured specific gravities of the materials in front of you matter more than typical figures. Everything in it is proportioned at saturated surface-dry.

Real stockpiles are wetter or drier, and correcting the batch for that is a separate step that comes after the design rather than inside it. The procedure ends at a trial batch, not at a number: the mix is mixed, measured for slump, air, density and strength, and adjusted from what it actually did.

Nothing it produces on paper establishes a strength, and what strength is required and for which exposure arrives from the design code and the project specification rather than from here.

Obtained from American Concrete Institute. What ACI publishes

This site holds no edition list for ACI 211.1, so a citation here names ACI 211.1 rather than a year. The publisher above has the current designation.