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CONCRETE TECHNOLOGYwww.cpi-worldwide.com CPI %u2013 Concrete Plant International %u2013 5 | 2025water content - no more than %u0394WNullk,38cm = 4.0 kg/m%u00b3. In contrast, changing the fine aggregate results in a difference of up to %u0394WNullk,38cm = 26 kg/m%u00b3 at a cement content of 360 kg/m%u00b3.5 Use of superplasticizerModern construction concretes almost routinely contain plasticizing admixtures to improve workability or to reduce water content while maintaining the same workability [15]. The products used can generally be classified into the product groups of polycondensates and polycarboxylates. The effectiveness of polycondensates, which work based on electrostatic effects, may be insufficient to liquefy modern low-water concretes. For such concretes, admixtures based on polycarboxylate ethers (PCE) are primarily used. These admixtures possess an electrosteric mechanism of action and are characterized by a high structural variety. This allows PCE-based plasticizers to be chemically tailored to the diverse requirements of concrete technology and construction processes [16]. Figure 6 shows guideline values for a possible reduction in water content when using different types of plasticizing admixtures. It should be noted that these guideline values are based solely on practical experience and can vary depending on the product type. To better contextualize them, a range of values is provided, indicating minimum and maximum water content, primarily resulting from the influence of the particle composition or fine aggregate.Considering the zero-consistency values (WNullk,38cm) shown in Figure 5, which correspond to the necessary water content to achieve a slump flow of 38 cm (F2), it becomes apparent Fig. 5: Determined zero-consistency values (WNullk,38cm) of the concrete mixtures shown in Fig. 4 - water content in fresh concrete (3-component system, without chemical plasticizing admixtures) required to achieve a slump flow of 38 cm.cds-concrete.com hsanlagentechnik.comcds-concrete.comCONCRETE CURING SYSTEMShsanlagentechnik.comCONCRETECURING & RACKINGSOLUTIONS