RESEARCHING THE INFLUENCE OF PLASTICIZERS ON THE TECHNOLOGICAL AND PHYSICAL-MECHANICAL PROPERTIES OF COMPOSITE BINDING SUBSTANCES OF THE СаО – Al2O3 – SO3 – H2O SYSTEM

Abstract

Problem statement. Composition of modern concretes and mortars includes surface-active substances that regulate processes of hydration, structure formation and, accordingly, properties of artificial stone. One of the types of surface-active substances are plasticizers, their main purpose is to reduce water consumption. When considering their influence, a wider range of changes in the properties of solutions and concretes can be noted. In this regard a particular attention should be paid to aluminate, sulfate and sulfo-aluminate binders. Therefore, the development of composite binders of the CaО – Al2O3 – SO3 – H2O system based on alumina cement and gypsum with the use of plasticizers requires research in this direction. The purpose of the article – to investigate the effect of plasticizers on the technological and basic physical and mechanical properties of alumina cement and composites based on it. Conclusions. A complex of experimental and statistical models of nanomodified compositions based on alumina cement and gypsum was obtained, and these models make it possible to determine influence of input factors on the growth of the main physical and mechanical properties. Research has established the ratio of the basic components of the composite based on 70 % alumina cement, 30 % gypsum and Sika VG Sika plasticizer = 0.10 ÷ 0.40; alumina cement = 69.72 ÷ 69.93; Gypsum = 29.88 ÷ 29.97. According to the manufacturing technology, the number of components was reduced to a minimum and a binder-filler-plasticizer system was obtained. From the economic point of view, depending on the customer’s requirements, it is possible to regulate the consumption of alumina cement and gypsum binder within the limits of approximately 10 %.