Comparative Analysis of Abrasiveness, Density, and Water Absorption of Laterite Interlocking Bricks and Rice Husk Ash Sandcrete Blocks in Acidic Environment

Abstract

Nigeria's housing affordability issues demand innovative and, sustainable building materials. Rising costs of traditional materials used in the production of sandcrete block such as, cement necessitate the need for alternative ingredients, such as partial cement replacement using rice husk ash and laterite. Nevertheless, the Nigerian Delta region is exposed to acidification due to gas flaring and human activities, raising considerable concerns as highly acidic rain threatens the durability performance of building. The durability of Rice Husk Ash Sandcrete Blocks (RHASB) and Laterite Interlocking Bricks (LIB) under acidic conditions remains uncertain. This study examined the effects of Tetraoxosulphate (VI) acid on RHASB and LIB. Laterite Soil was obtained from Olomi Ogbomoso (80 14.41 2.211N and 40 22.31), RHA was obtained from a rice mill in Ajase, Offa, Kwara State (80 121 1511N and 40 481 12.311 E). RHA blended cement was thoroughly mixed on site. Acid concentrations at pH 3.0, 3.5 and 4.0 were prepared. Water with pH value of 7.0 was used as control. LIB and RHASB were produced and immersed in acid solutions for 3, 7, 14, and 28 days. The abrasiveness, density and water absorption of the samples were measured. The percentage of abrasiveness for RHASB at pH 3.0, 3.5, 4.0, and 7.0 were 4.34, 3.62, 3.55, and 2.87%, respectively. The corresponding values for LIB were 10.94, 10.39, 8.54, and 6.84%, respectively. The density of RHASB at pH 3.0, 3.5, 4.0, and 7.0 were 1,074, 1,076, 1,081, and 1,138 kg/m3 at 7, 14, 21 and 28 days, respectively. The corresponding values for LIB were, 3,886, 4,038, 4,141, and 3,493 kg/m3, respectively. The water absorption of RHASB was 3.3%, and LIB was 6.7%. LIB exhibit better performance in Tetraoxosulphate (VI) solution. However, both samples of RHASB and LIB lost more weight at lower pH, showing decreased durability in Tetraoxosulphate (VI) solution. LIB exceeds density minimum requirements and its better suited for high-density, stable applications in acidic environments.