Zabihollah Tahery, Shigeyuki Date Article first published online: 2017 Abstract
The objective of this study was to investigate the interaction of different types of cement and superplasticizer admixtures in which the Superplasticizers were stimulated by heating before addition to the mortar. To evaluate the desired impacts, tests on the fluidity and flow loss of mortar were conducted. For better considering the behavior of admixtures under heat stimulation with different types of cement, three types of cement and two types of superplasticizer are used, Polycarboxylic acid-based and Polycarboxylic acid-based ether. The admixtures were heated to 40 ̊C, 50 ̊C, and 60 ̊C for 0.5 hours and 24 hours. Generally, Polycarboxylic acid-based admixtures showed higher flow improvement in 60 ̊C heating with all cement types, especially with High Early Cement, in comparison with Polycarboxylic acid-based ether type. The flow loss of mortar was reduced by heat stimulation of admixtures, Polycarboxylic acid-based ether (the product suitable for Ready Mix Concrete) showed significant flow improvement after 15 minutes and kept it to one hour. As the result of this research, it is possible to reduce the admixture dosage and maintain the desired fluidity of mortar or increase the mortar fluidity by applying the heat stimulation technique. |