Concrete Mix Design Using Available Coarse Aggregate in Yola, Adamawa State

Abstract

This study examines the physical properties and the compressive strength characteristics of two samples of available coarse aggregate in Yola metropolis which were identifred as Basalt and Granite. Design mixes were produced using the coarse aggregates at water-cement ratio of 0.45, 0.50 and 0.55, concrete mix proportion in ratiol:l:3 and 1:2:3 was achieved and the workability checked. Concrete cubes were cast with target strength of 30N/mm2 cit 28 days hydration. Result obtained shows that compressive strength increase in age of curing and decreased with increase in fine aggregate content and water cement ratio.lt was faund that concrete cubes made with sample I aggregate (Basalt) have lower compressive strength than those made with sample II aggregates (Granite) at a given water cement ratio,fine aggregate content and curing age. All the cast cubes attained 55-63% of their 28 days strength at 7 days. lt was established that at 28 days hydration, sample I cubes attained the strength of 29.7 N/mm2 while sample II cubes attained the strength of 31.30N/m at water cement ratio of 0.45. Based on the above findings, the study recommends concrete mix proportion in ratio 1:1:3 and 1:2:3 at water cement ratio of 0.45 for Yola's coarse aggregates to achieve the needed workability and target strength of 30N/mm2.