Strength assessment of concrete made from coastal plain sands: a case study of part of southwestern Nigeria

The compressive strength properties of concrete with varying proportions of Coastal Plain Sands (locally referred as 'Yoyo' sand) as substitute in fine aggregate as well as different mix proportions were studied. Three mixes (batching by weight) of 2:3:6; 1:2:4 and 1:3:6 were used with water/cement ratio of 0.55, 0.65 and 0.75 respectively. Test results showed that the fine aggregate is generally of high quality in terms of compressive strength and bulk density and it also produced concrete of relatively high compressive strength especially with mix 2:3:6 and 1:2:4 which have compressive strength varying from 16.6 N/mm2 to 29.1 N/mm2 and 12.9 to 23.2 N/mm2 respectively and slump values ranging from 5mm to 97mm. This is an indication that Coastal Plain Sands are suitable for the production of concrete, either wholly or by partial substitution with conventional river sands. Concretes produced from mix 1:3:6 exhibited relatively lower compressive strength due to low quantity of cement mix and water/cement ratio of 0.75.