Mechanical Properties of Concrete using Bida Natural Aggregate as Coarse Aggregates

Abstract

Significant volume of concrete is occupied by aggregates. Most of these are obtained from rock fragment which depletes natural resources and thereby distorting the ecosystem. The use of alternative aggregate has the potential of reducing this menace. This paper investigates the slump and strength properties of concrete made by varying Bida Natural Aggregate to total aggregate ratio (BNA/TA). Nine different mixes were prepared for three Water to Cement (W/C) ratios and three BNA/TA ratios while Total Aggregate to Cement ratio (TA/C) was kept constant. Properties of the aggregates were determined and found to be satisfactory for concrete production. Three 150x150x150 mm concrete cubes, three 100x100x500 mm concrete prisms and three 100x200 mm concrete cylinders were produced for W/C of 0.4, 0.5 and 0.6 and BNA/TA of 0.55, 0.6 and 0.65. The compressive strength, flexural strength and splitting tensile strength of the specimens were determined at 28 days curing duration. Test results indicates that the higher the BNA /TA content, the lower the slump of concrete. A combination of BNA/TA of 0.55, W/C of 0.4 and TA/C ratio of 3 gave maximum compressive, flexural and splitting tensile strength of 44.30 N/mm2, 7.60 N/mm2 and 3.42 N/mm2 respectively. It was concluded that BNA can be used in place of crushed granite in concrete production.