Physical and mechanical properties of Odukpani dolerites, southeastern Nigeria

The physical and mechanical properties of dolerite intrusives of Odukpani town in the Calabar Flank, southeastern Nigeria were determined to ascertain their suitability as construction aggregates. The results indicate that specific gravity (SG) ranges from 2.76 – 2.98, density 2.77 g/cm³ – 3.30 g/cm³, porosity 0.12% – 0.15%, water absorption 0.26% – 0.60%, abrasion resistance 4.60% – 6.64% and Schmidt hardness 33.60 N/mm² – 34.70 N/mm² and uniaxial compressive strength 100 – 178 N/mm². The low porosity and water absorption values coupled with a low fracture density and high strength within the Odukpani dolerite make it suitable for construction works as the rate of physical breakdown of the rock and alteration of its primary minerals would be low. Considering the dominance of ferromagnesian minerals in dolerites, proper treatment is required if it must be applied in heavy construction works but it can be readily used as aggregates for concrete, light foundation loads and other indoor construction as its physical and mechanical properties make it of good quality.