Hydric and durability performances of compressed earth blocks stabilized with industrial and agro by-product binders: calcium carbide residue and rice husk ash

This study investigated the hydric and durability performances of compressed earthblocks (CEBs) stabilized with calcium carbide residue (CCR) and rice husk ash (RHA).Dry mixtures were prepared using kaolinite‑rich earthen material and 0 to 25 % CCR or20:0 to 12:8 % CCR:RHA of the weight of earth. Moistened mixtures were manuallycompressed to produce CEBs (295x140x95 mm). Stabilized CEBs were cured at30±5 °C, wrapped in plastic bags for 45 days. The cured CEBs were dried and testedfor water absorption and other indicators of durability. Unstabilized CEBs immediatelydegraded in water. The stabilized CEBs were stable in water, with very low coefficientof capillary absorption (<20 g/cm².min 1/2 ) and excellent durability indicators. Theyresisted erosion at standard water pressure (50 kPa) and at a pressure of 500 kPa.The coefficient of surface abrasion improved far higher than 7 cm²/g recommended forthe construction of facing masonry. It also increased after wetting‑drying cycles andcorrelated with the evolution of compressive strength. This correlation can be used asthe non-destructive test of stabilized CEBs