Thermomechanical characterization and modelling of sodium silicate impregnated hemp concrete

Hemp concrete is a sustainable bio-based material whose low mechanical strength limits its use in construction applications. This study aims to enhance its performance through impregnation with sodium silicate solutions at various concentrations. The results demonstrate a significant improvement in mechanical properties and moisture buffering capacity, while preserving thermal performance. At an optimal concentration of 85%, compressive strength increases by 143%, elastic modulus by 368% and moisture buffering capacity by 44.7%. Furthermore, a finite element model complements the experimental approach and shows good agreement with the measured mechanical properties. Numerical results indicate that the Implicit scheme in Abaqus provides more accurate predictions (1–3% deviation) than the Explicit scheme (11–18% deviation). These findings confirm the potential of sodium silicate-treated hemp concrete for applications in non-load-bearing elements, prefabricated panels and sustainable insulation systems. • Sodium silicate impregnation enhances the mechanical and hygroscopic performance of hemp concrete while preserving bio-based thermal properties. • Microstructural densification increases Young’s modulus and compressive strength, with optimal results at 85% concentration. • The treated material is suitable for non-load-bearing elements, prefabricated panels, and insulating blocks. • Finite element modelling agrees well with experimental mechanical results.