Characterisation of Locally Sourced Aggregates for Concrete Production in Plateau State

The quality of locally sourced aggregates significantly influences concrete strength and durability, yet systematic characterisation of aggregates from quarry sources in Plateau State, North Central Nigeria, remains inadequate for informed construction practice. This study characterises coarse and fine aggregates from three active quarry sites in Jos North, Barkin Ladi, and Shendam Local Government Areas of Plateau State. Aggregate samples were collected and subjected to standard laboratory tests including sieve analysis, specific gravity, bulk density, aggregate crushing value, aggregate impact value, water absorption, and flakiness and elongation index. Results were assessed against BS EN 12620 and ASTM C33 standard specifications. Coarse aggregate from the Jos North quarry recorded the highest aggregate crushing value of 28.4 percent, marginally above the 25 percent recommended maximum for use in high-strength concrete. Shendam aggregates showed the most favourable grading curve with elongation index within the 15 percent maximum. Water absorption ranged from 0.8 to 2.4 percent across sources. Fine aggregate fineness moduli ranged from 2.3 to 2.9, indicating medium to coarse gradations suitable for structural concrete. Specific gravity values of 2.61 to 2.72 are consistent with granite-based aggregates. The study concludes that aggregates from all three sources are suitable for ordinary structural concrete production with appropriate mix design adjustments. It recommends that contractors source aggregates from Shendam and Barkin Ladi quarries for premium structural work and verify aggregate properties before each major project.

Keywords: aggregate characterisation, concrete production, quarry aggregates, Plateau State, North Central Nigeria