Effect of superabsorbent polymers, superplasticizer and additional water on the setting of cementitious materials

Superabsorbent polymers (SAPs) are particles which can take up a significant amount of fluid without dissolving and are already applied in cementitious materials. Water or superplasticizer needs to be added to compensate for the loss in workability, but both have an effect on several properties. In this paper, the effect on the setting of cementitious materials was compared for mixtures with (out) SAPs, with(out) superplasticizer and with(out) additional water. The mixing properties were quantified by means of flow tests, and the setting by ultrasonic transmission measurements and penetration tests. SAP particles reduce the flow but do not seem to influence the setting time. The used superplasticizer did have a pronounced effect on the setting, as the setting time was shifted for several hours. Additional water did not induce this effect and the setting was comparable to the reference mixture.