The British method of concrete mix design, popularly referred to as the "DOE method", is used in the United Kingdom and other parts of the world and has a long established record. The method originates from the "Road Note No 4" (see References 1), which was published in Great Britain in 1950. In 1975 the note was replaced by the "Design of Normal Concrete Mixes", published by the British Department of the Environment (DOE). In 1988 the "Design of Normal Concrete Mixes" was issued in a revised and updated edition to allow for changes in various British Standards (see References 2).
Firstmix is generally based on the recommendations and data contained in this edition. Its Tables and Figures are incorporated in Firstmix as data, which are stored for discrete values, and linear interpolation is employed to obtain intermediate values.
The DOE method utilizes British test data obtained at the Building Research Establishment, the Transport and Road Research Establishment, and the British Cement Association. The aggregates used in the tests conformed to BS 882 (see References 5) and the cements to BS 12 or BS 4027 (see References 3 & 4).
The DOE method is based on various assumptions and requirements:
On the basis of tests the DOE Method provides a Table and a Figure from which one can estimate the free water/cement ratio, which will provide a given strength for concrete made from given coarse aggregate and cement types.
On the basis of tests the DOE Method provides a Table from which on can estimate the free water content, which will provide a given workability for concrete made from given fine and coarse aggregate types and a given maximum size of coarse aggregate.
On the basis of tests the DOE Method provides Figures from which on can estimate the percentage of fine aggregate, which for given a free water/cement ratio will provide a given workability for concrete made from fine aggregate of a given grading.
The DOE Method also provides guidance on the effects of air entrainment in a concrete mix.
The DOE Method divides concrete mix design into five stages.