Increasing the performance characteristics of Aerated Concretes through the use of composite additives

Abstract

The article examines the prospects for improving the performance of non-autoclaved aerated concretes through the use of mineral and chemical composite additives. The relevance of using such modifiers is substantiated in the context of modern construction requirements, particularly under conditions of intensive urban development and the urgent need for rapid housing restoration. It has been established that the incorporation of microsilica, metakaolin, finely ground blast-furnace slag, superplasticizers, and hardening accelerators contributes to the formation of a dense, uniform, and thermally stable microstructure of the cement matrix, which significantly affects the operational properties of the final material.

Experimental studies have shown that the use of these additives enables a substantial reduction in the water-to-cement ratio (down to 0.31–0.33), a 4–5-fold decrease in shrinkage, lower thermal conductivity, and a 2.3–2.8-fold increase in compressive strength compared to the control sample. The most effective results were achieved by combining microsilica with a superplasticizer and a hardening accelerator, which ensured the formation of a stable fine-pored structure with evenly distributed pores measuring 20–200 μm. The formation of dense inter-pore partitions was observed, which improved thermal insulation and reduced water absorption.

The obtained results confirm the feasibility and practical effectiveness of such technological solutions for the production of energy-efficient, durable, and lightweight next-generation construction materials. The use of modified non-autoclaved foam concrete is especially relevant for enclosing structures, construction in severe climatic conditions, restoration of damaged housing stock, and fast-erecting buildings with enhanced thermal and energy efficiency requirements.