Mineralogical characterisation of tropical residual soils from south-western Nigeria and its impact on earth building bricks

Abstract

The mineralogy and chemistry of various lateritic soil samples were evaluated in this study. This was done with the aim of establishing the role of chemistry and mineralogy in the strength behaviour and durability of compressed earth bricks made from lateritic soils derived from different parent rocks. After establishing the geotechnical properties of the soils, which were found favourable, the soils were further subjected to X-ray diffraction and X-ray fluorescence analyses in order to identify the minerals and oxides present. The present study reveals the important role of silica and sesquioxides in the hardening of lateritic soil and the positive impact this hardening has on the strength and durability of compressed earth bricks. The study concludes that the mineralogy and chemistry of laterite, especially the presence of silica and sesquioxide, played a significant role in the cohesion and strength of bricks, giving rise to bricks with strength range of about 5.33–15.57 Mpa. Therefore, the produced bricks proved to be durable, withstanding unfavourable weather and climatic conditions over a period more than 18 months.