The materials should be thoroughly and efficiently mixed by means of forced action mechanical mixers, e.g. trough and pan paddle mixers and paddle mixers attached to screed pumps. The amount of water added should be the minimum necessary to give sufficient level of consistence for laying and thorough compaction.
To ensure uniform dispersion of admixtures, the measured dosage should be added to the water before mixing or at the same time as the water is added to the mix. When certain admixtures, e.g. superplasticizers, are added after mixing the concrete or levelling screed, the materials should be remixed thoroughly to ensure uniformity.