Hydrative reactivity of cement and rheological properties of fresh cement pastes

✍ Scribed by S. Grzeszczyk; L. Kucharska

• Publisher: Elsevier Science
• Year: 1990
• Tongue: English
• Weight: 621 KB
• Volume: 20
• Category: Article
• ISSN: 0008-8846
• DOI: 10.1016/0008-8846(90)90069-a

✦ Synopsis

The research results regarding rheological properties of industrial clinker pastes and their corresponding cement pastes are discussed. The flow curves and shear stress changes as well as the differences in clinker reactivity was determined. Interdependence was found to exist between clinkers reactivity, alkalis content, and the rheological properties of the corresponding cements. Moreover, it was also established that the more reactive clinker is due to increased reactivity of C3A cause by alkalis (potassium); the efficiency of gypsum as a bonding agent is lower and is apparent in a rapid consistency increase with time. This is particularly true for the cements under investigation whose K20 content is 0.70 -1.20% by weight and Na20 content is 0.10 -0.20% by weight, and whose degree of sulphatization is lower than 55%. In that case the increase of the degree of sulphatization of alkalis results in improved rheological properties. The consistency of cement pastes possessing similar mineralogical compositions and different alkalis content, was found to be related to the 28-day strength. Those cements of similar mineralogical composition whose pastes were characterized by the lowest consistency during the initial stage hydration, are found to reveal the highest strength.