Impact of hemp shiv content and binder type on the thermal and mechanical properties of geopolymer composites
Abstract
This study investigates the impact of incorporating hemp shiv (HS) fibers into geopolymer composites formulated with metakaolin (MK), coal combustion fly ash (FA1), and biomass fly ash (FA2) on their thermal and mechanical properties. HS content was varied (0, 200, 250, 300, and 350 wt% of the binder) to assess its effect on dry density, porosity, thermal conductivity, and microstructure. Results show that increasing HS content significantly increased porosity, leading to reduced density and thermal conductivity across all binder types. FA2-based composites exhibited the highest porosity (68.6%) and the lowest thermal conductivity (0.068 W.m -1 .K -1 ) at 350 wt% HS, reinforcing their suitability for thermal insulation applications. SEM analysis revealed substantial interfacial voids and cracking, particularly in FA-based composites, contributing to enhanced insulation properties but reducing compressive strength. Incomplete geopolymerization was observed in high-fiber-content composites, likely due to the absorption of activator solution by HS fibers, which affected matrix cohesion. Despite these structural changes, all composites remained within NF EN 998-1 standards for rendering and plastering mortars, with FA2-based composites demonstrating the greatest potential for thermal insulation applications, contributing to sustainability in construction.
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BibTeX
@article{nasreddine2026impact,
title = {{Impact of hemp shiv content and binder type on the thermal and mechanical properties of geopolymer composites}},
author = {Hussein Nasreddine and Nicolas Dujardin and Assia Djerbi and Thouraya Salem and Laurent Gautron},
journal = {Construction and Building Materials},
year = {2026},
month = sep,
doi = {10.1016/j.conbuildmat.2025.141297},
url = {https://univ-eiffel.hal.science/hal-05758829v1},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Impact of hemp shiv content and binder type on the thermal and mechanical properties of geopolymer composites
AU - Hussein Nasreddine
AU - Nicolas Dujardin
AU - Assia Djerbi
AU - Thouraya Salem
AU - Laurent Gautron
PY - 2026
DA - 2026/09/22
JO - Construction and Building Materials
DO - 10.1016/j.conbuildmat.2025.141297
UR - https://univ-eiffel.hal.science/hal-05758829v1
AB - This study investigates the impact of incorporating hemp shiv (HS) fibers into geopolymer composites formulated with metakaolin (MK), coal combustion fly ash (FA1), and biomass fly ash (FA2) on their thermal and mechanical properties. HS content was varied (0, 200, 250, 300, and 350 wt% of the binder) to assess its effect on dry density, porosity, thermal conductivity, and microstructure. Results show that increasing HS content significantly increased porosity, leading to reduced density and thermal conductivity across all binder types. FA2-based composites exhibited the highest porosity (68.6%) and the lowest thermal conductivity (0.068 W.m -1 .K -1 ) at 350 wt% HS, reinforcing their suitability for thermal insulation applications. SEM analysis revealed substantial interfacial voids and cracking, particularly in FA-based composites, contributing to enhanced insulation properties but reducing compressive strength. Incomplete geopolymerization was observed in high-fiber-content composites, likely due to the absorption of activator solution by HS fibers, which affected matrix cohesion. Despite these structural changes, all composites remained within NF EN 998-1 standards for rendering and plastering mortars, with FA2-based composites demonstrating the greatest potential for thermal insulation applications, contributing to sustainability in construction.
SN - 0950-0618
SN - 1879-0526
ER -