标题：Effects of alkaline and alkaline-earth ions on the rheological behavior and zetametric study of two cement pastes (artificial cement portland-CEMI and cement resistant to the sulfates-CRS) with the polynaphthalene sulfonate (PNS)
摘要：The use of admixtures which tends to be generalized in the formulation of self-compacting concrete (SCC), requires taking into account the chemical composition of cement, particularly its content of SO3, which can inhibit or restrain the effect of these admixtures (superplasticizers). For more information of the compatibility problem of cement-superplasticizer, the rheological tests with a rheometer-AR2000 and measurements of zeta potential with a Zêtasiser-2000 were used in this study. In order to understand this phenomenon due to the presence of SO3 in cement, we propose to evaluate the action of alkaline and alkaline-earth ions, incorporating different types of additions (K+, Na+, and Ca2+) to the cement pastes. To achieve this, our work will concern the study of rheological properties and physical characteristics of the pastes obtained using two types of cement (C1: Cement Resistant to the Sulfates (CRS) and C2: CEMI). This experiment will focus on two reports: Water/Cement (W/C) = 0.30 for which the polynaphthalene sulfonate (PNS) is used as superplasticizer and W/C = 0.50 (without superplasticizer). The results show that the presence of sulfate leads to different rheological behaviors which are function of sulfates and the cements used.
