Abstract
This paper provides a summary of the American Concrete Institute (ACI) design standards concrete mixture proportions for various exposure conditions in USA. As defined by ACI 318, for each class of concrete and exposure condition, minimum water to cementitious ratio and compressive strength, are prescribed. The responsibility of selecting the concrete mixture proportions design rest with a Professional Engineer, licensed in the State where the construction is carried out. Trial batches of concrete are performed in accredited laboratory, in accordance with ACI 211.1, with adequate lead time to ensure that the test results are available, prior to construction. Attention is given to selection of aggregate, cement type, supplementary cementitious materials (including fly ash and slag), air-entrainment, and the need for chemical admixtures for workability and durability requirements. A case study for a recent project, constructed in the USA, is discussed to provide guidance for appropriate selection of the concrete materials, mixture proportions consistent with the site and exposure conditions, including qualification tests. During construction, the fresh concrete properties were verified by testing slump. air content, unit weight, before placement. The variations in the delivered concrete properties (slump, air content, unit weight, etc.) from the specified requirements were dealt with through non-conformance reports for evaluation and resolution by a Professional Engineer.
Keywords
concrete proportions, industry standards, field quality control, non-conformance and resolution.
DOI
10.5703/1288284318100
Recommended Citation
Hasan, Nausherwan, "ACI Standards for Concrete Proportions, Qualification Testing and In-Process Testing during Construction" (2025). International Conference on Durability of Concrete Structures. 9.
https://docs.lib.purdue.edu/icdcs/2025/tmc/9
ACI Standards for Concrete Proportions, Qualification Testing and In-Process Testing during Construction
This paper provides a summary of the American Concrete Institute (ACI) design standards concrete mixture proportions for various exposure conditions in USA. As defined by ACI 318, for each class of concrete and exposure condition, minimum water to cementitious ratio and compressive strength, are prescribed. The responsibility of selecting the concrete mixture proportions design rest with a Professional Engineer, licensed in the State where the construction is carried out. Trial batches of concrete are performed in accredited laboratory, in accordance with ACI 211.1, with adequate lead time to ensure that the test results are available, prior to construction. Attention is given to selection of aggregate, cement type, supplementary cementitious materials (including fly ash and slag), air-entrainment, and the need for chemical admixtures for workability and durability requirements. A case study for a recent project, constructed in the USA, is discussed to provide guidance for appropriate selection of the concrete materials, mixture proportions consistent with the site and exposure conditions, including qualification tests. During construction, the fresh concrete properties were verified by testing slump. air content, unit weight, before placement. The variations in the delivered concrete properties (slump, air content, unit weight, etc.) from the specified requirements were dealt with through non-conformance reports for evaluation and resolution by a Professional Engineer.
