Strength investigation of modified vermiculite concrete

Abstract

This paper presents the results of an experimental investigation into the effect of combined admixtures -
superplasticizer, silica fume, and polypropylene fiber - on the mechanical properties of vermiculite-based
lightweight concrete. The aim of the study was to enhance the compressive and flexural strength of the
material while preserving its low density and thermal insulation properties. Three concrete mixtures with
varying combinations of admixtures were prepared and tested. The findings revealed that the use of silica
fume and superplasticizer increased compressive strength by up to 17%, while the addition of fiber further
improved it by up to 26% compared to the reference sample. Flexural strength also increased by up to
20%, highlighting the benefits of microstructural reinforcement. The results demonstrate the effectiveness
of the proposed composite modification approach, making the optimized vermiculite concrete suitable for
use in structural insulating components in construction.