Influence of superplasticizer type and dosage on the slump loss of Portland cement mortars -: Part II

Fluidity and slump loss are cardinal features responsible for the quality of concrete. These are related to the dispersion of cement particles and the hydration process, which are greatly influenced by superplasticizers (SPs). A variety of SPs are commercially available. Their influence on the fluidity and slump loss differs considerably. In this work, SPs based on lignosulfonic acid (LS), melamine formaldehyde sulfonic acid (SMF), naphthalene formaldehyde sulfonic acid (SNF), and polyacrylic acid polymer (CE) are tested with ordinary Portland cement (OPC) at different water-to-cement ratio. The results reveal that not only SPs of different base groups behave differently but even the SP of the same base group SMF behave differently. Fluidity increased with increase in the dosage of SP. CE was most effective followed by LS, SNF, and SMF SP. (C) 2002 Elsevier Science Ltd. All rights reserved.