Research of Modified Cementitious System for Non-Autoclave Aerated Concretes

The modern building construction technologies are based on the use of effective structural and thermal insulation materials with high technological, physical, mechanical and operational properties in accordance with requirements for energy effectiveness and thermal protection of buildings. The aerated concrete is characterized by such structural properties as low density, thermal conductivity, reduced self-load. It has been carried out investigation of properties and structure of cementitious system for non-autoclaved aerated concrete. It was established that the use of metakaolin and polycarboxylate superplasticizer accelerates the development of plastic strength of cementitious system to the level of 250 kPa from 109 min to 97 min. The adding of metakaolin into cementitious system allows to increase it strength after 28 days by 15.5% and adding of metakaolin and polycarboxylate superplasticizer—by 1.9 time. The possibility of directional regulation of the microstructure of partitions between pores due to directional phase formation of the modified cementitious system was revealed. The structurally active stability hexagonal hydrate products are formed as a result of the interaction between metakaolin, Portland cement hydration products and aluminium powder.