Page 280 - Handbook of Thermal Analysis of Construction Materials
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                              7





                              Superplasticizing


                              Admixtures













                              1.0    INTRODUCTION



                                     The advantages derived from the use of superplasticizing admix-
                              tures include production of concrete having high workability and produc-
                              tion of high strength concrete having normal workability and lower water
                              content. Another possible application is the fabrication of concrete with
                              less cement, having normal strength and workability. Superplasticizers
                              have also been used with advantage in concretes containing fly ashes, silica
                              fume, rice husk ash, slags, etc.
                                     A study of the hydration of cement and cement compounds in the
                              presence of superplasticizers is useful for theoretical and practical consid-
                              erations. Many types of thermal techniques including DTA, DSC, TG,
                              DTG, Conduction Calorimetry, and EGA have been used for such studies.
                              They have yielded important results that could be correlated with physical
                              and mechanical characteristics of cement systems. Investigations have
                              included the measurement of heat of hydration, the mechanism of reactions,
                              strength development, microstructure, permeability, durability aspects,
                              compatibility problems between cement and superplasticizers, the predic-
                              tion of some properties, material characterization and selection, math-
                              ematical modeling of hydration, development of test methods, and cement-
                              superplasticizer interactions.


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