Effect of Wood Biomass Ash on the Mechanical and Thermal Performance of Compressed Earth Bricks

This present study investigates the recovery of wood biomass ash (WBA) as chemical stabilize in compacted earth bricks. The specimens were tested for compressive and thermal properties in dry state. The tests were performed at 7 and 28 days of age in order to evaluate the effect of the partial substitution of soil with WBA on the mechanical and thermal properties of the compressed earth bricks. The results indicate that bricks manufactured with 20% of partial substitution showed better performance than those containing only soil. Nevertheless, the use of WBA as source of lime improved the compressive strength and the thermal conductivity of the bricks stabilized with different proportions (5, 10, 15 and 20% wt) when compared with bricks fabricated with 100% soil. This improvement is owing to the pozzolanic reaction produced between the soil components and the WBA as well as the soil microstructure. It was also concluded that the combination of the soil components and lime containing in WBA in the stabilization of compressed earth bricks seems to be a promising alternative when considering issues of energy consumption and pollution.