Akademik Veri Yönetim Sistemi
POWDER TECHNOLOGY, cilt.469, sa.1, ss.1-17, 2025 (SCI-Expanded, Scopus)
The increasing demand for sustainable and thermally efficient building materials has led to the development of lightweight geopolymer concrete (LWGPC) containing expanded vermiculite. This study focuses on the effects of fly ash (FA) replacement ratios (0 %, 50 %, and 75 %), NaOH molarities (12 M, 13 M, and 14 M), and expanded vermiculite particle sizes (fine [FV] and superfine [SFV]). Materials such as fly ash, perlite, and vermiculite are obtained from waste-based sources and are consistent with circular economy principles. Optimization scenarios were evaluated using Taguchi and ANOVA methods. The results show that the most influential parameter on density is NaOH molarity, while the type of expanded vermiculite plays a dominant role in compressive strength. FA content contributes to mechanical performance and thermal insulation, but has a relatively lower effect on density. Furthermore, samples containing expanded vermiculite exhibited flame resistance without any deformation or flow observed in the flame exposure test. Moreover, regardless of the particle size of the expanded vermiculite, an increase in FA content reduces thermal conductivity by up to 50 %. Microstructural analyses using FE-SEM and EDX revealed well-formed geopolymer matrices with aluminosilicate gel phases. This highlights the potential of expanded vermiculite-based geopolymer composites as lightweight, durable, and environmentally friendly alternatives in modern construction