Performance improvement of hemp-shiv cementitious composites through hot water and steam treatment

This research aims to economically reduce the waste disposal of hemp shiv by incorporating it into cementitious composites as a replacement for sand. Hot water and steam (H + S) pre-treatment of hemp shiv wastes was employed to mitigate their defects and improve the cementitious composites' mechanical properties. Morphological analysis revealed an alteration in the surface of hemp shiv from a smooth texture to a rough one when treated with H + S, which promotes better bonding with the cementitious binder, hence, improving the mechanical properties of the mortar. H + S treatment of hemp shiv assisted in reducing the flowability and increasing the wettability of the produced mortar. Moreover, changes in the surface chemistry and crystallinity of hemp shiv were observed due to treatment, which involved diminishing wax and polysaccharides and promoting lignin and hemicellulose levels. Mechanical properties investigation of hemp shiv mortars revealed a significant enhancement due to treatment, where a maximum of 62 % and 70 % increase in compressive and flexural strengths were achieved at 28 days.

Automated summary

The research aims to reduce waste disposal by incorporating hemp shiv into cementitious composites. Hot water and steam treatment improved the mechanical properties of the composites by altering the surface of hemp shiv and promoting better bonding with the cementitious binder. The treatment also resulted in changes in the surface chemistry and crystallinity of hemp shiv, leading to significant enhancements in compressive and flexural strengths of the mortar.