Hydric and Durability Performances of Compressed Earth Blocks Stabilized with Industrial and Agro By-Product Binders: Calcium Carbide Residue and Rice Husk Ash

Abstract

This study investigated the hydric and durability performances of compressed earth blocks (CEBs) stabilized with calcium carbide residue (CCR) and rice husk ash (RHA). Dry mixtures were prepared using kaolinite-rich earthen material and 0%–25% CCR or 20∶0% to 12∶8% CCR:RHA of the weight of the earth. Moistened mixtures were manually compressed to produce CEBs (295×140×95 mm). Stabilized CEBs were cured at 30°C±5°C and wrapped in plastic bags for 45 days. The cured CEBs were dried and tested for water absorption and other indicators of durability. Unstabilized CEBs immediately degraded in water. The stabilized CEBs were stable in water, with a very low coefficient of capillary absorption (<20 g/cm2·min1/2) and excellent durability indicators. They resisted erosion at a standard water pressure (50 kPa) and at a pressure of 500 kPa. The coefficient of surface abrasion improved far higher than the 7 cm2/g recommended for the construction of facing masonry. It also increased after wetting-drying cycles and correlated with the evolution of compressive strength. This correlation can be used as the nondestructive test of stabilized CEBs.