Fine-grained concrete with the addition of highly dispersed brick scrap powder

Abstract

The use of brick breakage in concretes and in binder compositions is a promising direction for the development of recycling ceramic bricks. The purpose of the present research was to evaluate the possibility of using mineral powders obtained from brick breakage as an effective dispersed component in the production of fine-grained concrete. In the work, mechanical grinding of ceramic raw material was carried out at different grinding times. It wasestablished that for brick-breakage powders, an increase in the grinding time does not lead to a proportional increase in the specific surface area of the powders.The maximum effective increase in the specific surface area of the obtained powders is fixed at a grinding duration of up to 5 minutes. Using differential thermal analysis, it is shown that crushed brick is not an active mineral additive, but can act as crystallization centers during the formation of hydrosilicates in the structure of composites. Samples of fine-grained concrete were produced, in which part of the cement was replaced with ceramic powders obtained at different grinding duration. It was determined that the replacement of cement in concrete mixtures with this highly dispersed additive in an amount of 20% (by weight), obtained at an optimal grinding time in a ball mill, does not lead to a change in the physico-chemical characteristics of the final concrete composite.