Verification of the application potential of the mathematical models of lyse, abrams and molinari in mortars based on cement and lime

Abstract

Cementitious materials have relevant applications related to the civil construction sector, such as concretes and mortars. However much of the existing technological research favors concrete, which makes mortar a still deficient material for research. The water / cement ratio is an extensively investigated parameter for concretes, however, it is still very little studied in mortar. The Abrams, Lyse and Molinari equations, for example, are consecrated in their application in concrete, but not yet evaluated for mortars, being a scientific gap. The objective of this work was to evaluate for the first time the effect of the water / cement ratio in mortars, using three different mixtures, in proportions of [1: 1: 6], [1: 2: 9] and [1: 0: 3] for cement: lime: sand combined with two different types of Portland cements. Based on these relationships the aforementioned equations investigating mortars were characterized. Mass consistency tests as well as mechanical resistance to compression and flexion test at 14 and 28 days as well as water absorption by capillarity and by immersion together with density measured in the hardened state were performed to verify the Abrams, Lyse and Molinari laws, and their possible validation for use in mortars. The results prove that the water / cement ratio considerably affects the evaluated technological properties and that the Abrams and Lyse equations are viable for application in mortars, just as they are applied to concretes. As for the Molinari equation, it requires mathematical modification, and the fresh mortars density.