Effect of temperature on the rheology of flowable mortars

In addition to the characteristics of mixture constituents and mix design, the theological behavior of concrete is influenced by material temperature and time after water-cement contact. The study presented herein evaluates the combined influence of time and temperature on the workability of micro mortars. The mixtures were proportioned with polymelamine (PMS), polynaphtalene (PNS), polycarboxylate (PCP) polymer, and made of different supplementary cementitious materials. Seven micro mortars proportioned with various binder compositions and water-to-binder ratio of 0.42 and 0.53 were prepared at 10-33 degrees C. Test results show that the yield stress and plastic viscosity vary linearly with the coupled effect of time and temperature for mixtures made with PNS or PMS superplasticizers. However, for mixtures made with PCP superplasticizer, both the material temperature and type of supplementary cementitious materials are shown to influence the evolution of rheology with time. (C) 2009 Elsevier Ltd. All rights reserved.