Performance of Concrete Incorporating Naka Lateritic Rock Fines as Partial Replacement of River Sand

Abstract

The search for sustainable and locally available materials for concrete production has increased interest in lateritic materials as alternatives to conventional aggregates. This study investigated the performance of concrete incorporating Naka Lateritic Rock Fine (NLRF) as a partial replacement for river sand. Concrete was produced using a mix ratio of 1:2:4 with a water-cement ratio of 0.58. River sand was replaced with NLRF at 0%, 25%, 50%, 75% and 100% by weight. A total of 45 concrete cubes and 45 cylinders were produced and cured for 7, 14 and 28 days. The aggregates were assessed for particle-size distribution and specific gravity, while the concrete was tested for workability, water absorption, density, compressive strength and splitting tensile strength. NLRF recorded a coefficient of uniformity of 3.40, coefficient of curvature of 1.20 and fineness modulus of 3.10, compared with 2.82 for river sand. Materials passing the 75 µm sieve were 3% for NLRF and 2% for river sand. Slump values ranged from 55–90 mm and generally decreased with increasing NLRF content. Specific gravity values were 2.53, 2.37 and 2.62 for river sand, NLRF and granite, respectively. Water absorption increased from 1.3% to 3.6%. Compressive and splitting tensile strengths ranged from 11.83–26.03 N/mm² and 1.92–2.63 N/mm², respectively. The 25% NLRF replacement produced the highest compressive strength of 26.03 N/mm² at 28 days and was identified as the optimum level. Therefore, the study recommends that 25% NLRF is suitable as a partial replacement for river sand in concrete production.