Effect of High Range Water Reducer (Type F) Admixture on Cement Paste Properties

Abstract

Thai cement industries have been increasingly utilized the concrete admixture on both of Ready MixConcrete (RMC) and Cement Production Manufacturing (CPM). Improving concrete qualifications shouldbe considered suitably on both of cement application and also costing. Therefore, this research indicatesto concrete admixture type F that impact to cement paste properties which were prepared from Portlandcement type III, including to advance research of concrete admixture for new type that can replace the oldone (Admixture A, B and C) to get economy advantage. The results showed that the main compound ofadmixture A is Melamine Sulphonate, the main compound of admixture B is Naphthalene Sulfonate andthe main compound of admixture C is Polycarboxylate type. The prepared admixture mixed with concrete10% polycarboxylate about 1% by weight has flow of cement paste of mortar 119% and slump of concrete(W/C = 0.38) at 7 centimeters. After increasing 2% by weight, flow of cement paste = 124% and slumpof concrete (W/C = 0.38) at 8 centimeters, which better than the prepared admixture and market samplesbecause polycarboxylate base component dispersed in cement paste particles causes uniform size and someettringite structure which increase hydration reaction. Therefore, 1% by weight of the prepared admixturehas less cost than A, 10 baht/m3.

Keywords : Ready Mix Concrete / Concrete Admixture / Flow of Mortar / Slump of Concrete