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CONCRETE TECHNOLOGYwww.cpi-worldwide.com CPI %u2013 Concrete Plant International %u2013 5 | 2025aggregate size - and thus the differing water demands of the aggregate compositions %u2013 to be eliminated. The previously described large scatter in the data is significantly reduced, as the properties of the aggregates are integrally accounted for in the calculated values for Vw,flow. As a result, the consistency of fresh concrete can be reliably estimated for different constituent materials and mix designs based on the determined values for Vw,flow. Using the properties of the aggregate, it is possible to predict the amount of mixing water required to achieve a certain target consistency. For example, to achieve a slump flow of 45 cm, approximately 115 l/m%u00b3 of effective water Vw,flow is needed for fluidization of the mix.It should be noted that the considerations described above apply exclusively to the conventional 3-component or 4-component systems (including supplementary materials). The use of plasticizing admixtures, which is common practice today for adjusting consistency, is not accounted for in these observations. 4 %u201cZero-consistency%u201cTo achieve the desired consistency using plasticizing admixtures, a sufficient paste content in the fresh concrete is necessary. Thielen et al. [14] have already shown that fresh concretes can only be fluidized with admixtures if the paste content is sufficient to completely fill the voids between the aggregate particles. Only then can the reduction in the shear resistance of the paste take effect and allow the individual aggregate particles to move past each other. If there is not enough paste and hence the voids between the aggregates Fig. 3: Water available for fluidizing the fresh concrete (Vw,flow), shown here as a function of the resulting slump flow for different concrete mixes with maximum aggregate sizes of 8 mm, 16 mm, and 32 mm.