CONCRETE

UDC 666.97:691.3

[:en]Egorov E. S.[:ru]Егоров Е. С.[:] [:en]Postgraduate student, Moscow State University of Civil Engineering, Moscow, Russia; Senior Lecturer, Yaroslavl State Technical University, Yaroslavl, Russia[:ru]аспирант, Национальный исследовательский Московский государственный строительный университет, Москва, Россия; ст. преподаватель, Ярославский государственный технический университет, Ярославль, Россия[:]

[:en]Samchenko S. V.[:ru]Самченко С. В.[:] [:en]Doctor of Technical Sciences, Professor, Moscow State University of Civil Engineering, Moscow, Russia[:ru]д-р техн. наук., профессор, Национальный исследовательский Московский государственный строительный университет, Москва, Россия[:]

[:en]Abramov M. A.[:ru]Абрамов М. А.[:] [:en]Candidate of Technical Sciences, Associate Professor, Yaroslavl State Technical University, Yaroslavl, Russia[:ru]канд. тех. наук, доцент, Ярославский государственный технический университет, Ярославль, Россия[:]

Alitinform №3 (68) 2022 г. 42-54 p.

Abstract

The article considers the possibility of using a sludge water extracted in recycling technology from waste concrete mixture. A pre-hydrated cement slurry was adopted as a model. It is considered both as the chemical modification option and the hydrodynamic activation of the suspension in a rotary pulsation apparatus were considered. Slurry water is proposed to be used as an additive in a new concrete mix. In this regard, its influence on the rheological properties of the mixture (water demand), as well as technological (setting time) and physical-mechanical (compressive strength and porosity of cement stone) was investigated. The phase composition of cement stone was investigated after a day of hardening. As a result of the study, an increase in the water demand of the mixture was found, the possibility of a significant reduction in water demand due to activation together with a superplasticizer was proposed and proved. The mixture with the activated additive was characterized by shortened setting times, as well as a rapid set of early strength (for 1 and 3 days), which allows us to judge the receipt of fast-hardening cement.

Key words:

recycling of concrete mixes, hydrodynamic activation, rotary pulsating apparatus