Mathematical Models of the Effect of Colloidal Surfactants on the Strength of Alkaline Concrete

Abstract

Under certain conditions, an increase in the rate of hydration of the binding substance increases the strength of concrete at compression. This is especially true for the reactive powder concretes. We studied the effect of surface-active substances, capable of forming micelles, on the rate of formation and the resulting magnitude of strength at compression of the alkaline reactive powder concretes. A particular feature of our research was studying the simultaneous action of surface-active substance that forms micelles and a reactive powder or a filler on the change in the strength of concretes. It was found that the specified micellar solutions and reaction powders change the character of formation of strength of the alkaline reactive powder concretes. The rate of strength formation over the early stages increases due to the micellar catalysis of hydration of blastfurnace granular slag, while their enhanced compressive strength is maintained at the late stages of hardening. Strength of the alkaline reactive powder concretes, when applying the surface-active substances that form micelles, reaches 260% of the strength of such concretes without any additives. It was proved that the micellar catalysis could be used to control the hardening processes of a binding substance, consisting of blast-furnace granular slag and an alkaline component, and to form the strength of the resulting artificial stone. That shortens the time required for concrete to achieve the designed strength and improves the absolute magnitude of the compressive strength of such concretes at the age of 28 days.