ACI 211.1-91 Standard Practice for Selecting Proportions for Normal, Heavyweight, and Mass Concrete
Reported by ACI Committee 211
Describes, with examples, two methods for selecting and adjusting proportions for normal weight concrete, both with and without chemical admixtures, pozzolanic, and slag materials. One method is based on an estimated weight of the concrete per unit volume; the other is based on calculations of the absolute volume occupied bythe concrete ingredients. Theprocedures take into consideration the requirements for placeability, consistency, strength, and durability. Example calculations areshown for both methods, including adjustments based on the characteristics of the first trial batch. Theproportioning ofheavyweight concrete for such purposes as radiation shielding and bridge counterweight structures is described in an appendix. This appendix uses the absolute volume method; which is generally accepted and is more convenient for heavyweight concrete. There is also an appendix that provides information on the proportioning of mass concrete. The absolute volume method is used because of its general acceptance.
This Standard Practice describes methods for selecting proportions for hydraulic cement concrete made with and without other cementitious materials and chemical admixtures. This concrete consists of normal and/or highdensity aggregates (as distinguished from lightweight aggregates) with a workability suitable for usual cast-in-place construction (as distinguished from special mixtures for concrete products manufacture). Also included is a description of methods used for selecting proportions for mass concrete. Hydraulic cements referred to in this Standard Practice are portland cement (ASTM C 150) and blended cement (ASTM C 595). The Standard does not include proportioning with condensed silica fume.
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