Artificial aggregates based on granulated reactive silica powders

•The artificial aggregates based on granulated SiO2 reactive powders for LWA concrete were developed.•It was demonstrated that the optimal alkali content in the aggregate core can vary from 10% to 30%.•The sodium polysilicate solutions formed under steam treatment density the aggregate contact zone.

This paper reports on the development of artificial aggregates based on granulated reactive silica (AAGS) powder materials activated by alkaline components. The alkali content was optimized depending on the properties of the reactive silica (RS) material. The best RS component for AAGS was determined to maximize the volume of synthesized soluble polysilicates. Additional research was conducted to evaluate the materials for the formation of a strong shell for AAGS. The effect of RS and AAGS composition on the structure of hardened cement composite was investigated.

Graphical abstractThe transformations of mineral composition of opoka-based aggregate core due to thermal treatment: before (1) and after heat treatment (2) (СТ – crystobalite–tridymite bearing opals; Q – quartz)Figure optionsDownload full-size imageDownload as PowerPoint slide