Influence of method and duration of curing and of mix proportions on strength of concrete containing laterite fine aggregate

In this paper, the influence of six curing methods (water, air, moist soil, jute bag, air/water and water/air) on the compressive strength of concrete cube specimens that contain laterite fine aggregate is investigated. Three different mixes of cement, laterite and gravel were used: ; 1:2:4 and 1:3:6 with water/cement ratios of 0.62, 0.75 and 1.02 by weight respectively. Four curing ages of 7, 14, 21 and 28 days were adopted. The results showed that the strength that a particular mix can attain is affected by the curing method used. The water/air curing technique gave the highest strength values of 28.2 Nmm⁻² for Nmm⁻² and 17.4 Nmm⁻² for 1:2:4 and 1:3:6 mixes respectively, while the air-cured specimens gave the lowest strength values of 17.2 Nmm⁻² for Nmm⁻² and 8.0 Nmm⁻² for 1:2:4 and 1:3:6 mixes. The higher the cement/aggregate ratio the higher the strength. Generally, there was increase in strength with age irrespective of the mix and the curing technique.