Evaluation of the influence of a superplasticizer on the hydration of varying composition cements by the electrical resistivity measurement method

Abstract

Electrical resistivity measurement was employed to study the influence of varying dosages of a superplasticizer on the hydration process of cements with different chemical composition. The electrical resistivity development curves as a function of time for all cement pastes were explained in detail. The electrical resistivity rate curves of the cement pastes were compared, and the results indicate that electrical resistivity measurement by a non-contact method is a sensitive monitoring technique for cement hydration and microstructure development. Much information related to the effect of superplasticizers on the properties of cements differing in composition can be provided by this method, helping mix designers to define more appropriate use of admixtures. Based on the electrical resistivity development behaviour of the samples, and other findings, the superplasticizer used has a more effective dispersive force and more influential retardation effect, in addition to a less bleeding trend in case of the 42.5 class of cement compared to the 32.5 class with the same water-to-cement ratio and curing conditions.