Impact of hemp shiv content and binder type on the thermal and mechanical properties of geopolymer composites
Year: 2025
Type: article
Abstract: This study investigates the impact of incorporating hemp shiv (HS) into geopolymer composites made from metakaolin (MK), fly ash (FA1), and biomass fly ash (FA2) on their thermal and mechanical properties. FA1 is composed entirely of 100% fly ash from combusted coal, while FA2 is a mixed ash, consisting of 70% fly ash from combusted coal and 30% biomass ash derived from agricultural residue. The experimental work varied the fiber content (0, 200, 250, 300, and 350 wt% of the binder) and examined changes in dry density, thermal conductivity, and porosity. Results show that adding HS significantly increases total porosity and reduces dry density and thermal conductivity. MK-based composites without added fibers (0MK) exhibited the lowest initial porosity (28.6%) and the highest density (1442 kg/m3). In contrast, FA2-based composites with the highest fiber content (350 wt%) demonstrated the highest porosity (68.6%) and the lowest density (235 kg/m3). Thermal conductivity decreased notably, with FA2-based composites dropping from 0.395 W.m-1.K-1 for 0 wt% HS to 0.068 W.m-1.K-1 for 350 wt% HS. The study provides a comparative analysis of MK, FA1, and FA2-based geopolymer composites with high HS content, concluding that FA2-based composites are particularly suited for thermal insulation applications, promoting sustainability in construction.
Language: English
Subfield: Building and Construction
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $4,540
OpenAlex ID: W4409445737