Enhancing the Properties of Soil Bricks by Stabilizing with Corn Husk Ash

Abstract

A study was conducted to investigate the potential of corn husk ash as an enhancer for the production of soil blocks for low cost housing. Five different levels of stabilisation (0%, 5%, 10%, 15% and 20%) using corn husk ash were adopted for this study. Fifteen blocks were moulded for each stabilisation level. In all a total of 75 blocks were moulded and subjected to the compressive strength, abrasion resistance and water absorption by capillarity tests after curing for 28 days and compared with the relevant standards of compressive earth blocks. In general, there was a significant improvement in the compressive strength characteristics of the stabilized soil blocks. From the compressive strength test results, compressive strengths of 4.177MPa, 4.380MPa and 4.053MPa were obtained for blocks admixed with 0%, 5% and 10% corn husk ash respectively. Soil blocks mixed with 20% corn husk ash had the highest compressive strength of 5.311MPa followed by blocks which had 15% corn husk ash addition also with a compressive strength of 4.917MPa. The water exclusion and the abrasion resistance properties also showed significant improvement as the quantity of corn husk ash increases. There was a significantly strong negative correlation of 0.754 existed between the abrasion coefficients and the water absorption coefficients of the soil blocks. Stabilizing of soil with corn husk ash can improve the properties of soil  and soil blocks making the suitable for use as a building material for the construction of load bearing walls.

Keywords: Corn husk ash, Soil stabilised brick, Abrasion resistance, Water absorption by capillarity, Compressive strength