PHYSICAL AND THERMAL CHARACTERIZATION OF CEMENTITIOUS COMPOSITES BASED ON PLANT-BIOMASS

This paper presents the results of an experimental study on the evaluation ofphysical and thermal properties of cementitious composites based on plant biomass (rice husks and palm tree fibers). Composites produced are cement mortars with total replacement of sand by aggregates of rice husks (B) or palm tree fibers (F). Three cement content (D₁, D₂ and D₃) and two granulometries of biomass (coarse mixture and fine mixture) were used for the manufacturing of studied samples. After 28 days of curing, dry density, water absorption by capillarity and thermal conductivity of mortars were measured. The results show that dry density and thermal conductivity of composites increase with cement content while water absorption by capillarity decreases with an increase of cement content regardless of biomass size particle. In addition, thermal conductivity increases with dry density and decreases with water absorption by capillary. For all studied mixtures, composites based on palm tree fibers give better results (high dry density, low water absorption coefficient and low thermal conductivity) than those based on rice husks. The results also indicate that the replacement of sand by aggregates of rice husks or palm tree fibers in mortars is an interesting option to be considered to produce new materials with low thermal conductivities (less than 0.50 W/mK).