Secant modulus of concrete containing Itapke Iron ore tailings as partial replacement of sand

Abstract

Abstract Natural sand is the conventional fine aggregate material in concrete production. Due to depletion of the environment, more and more plants are removed (erosion), this leads to gradual reduction in natural sand. Also there is increasing demand for sand due to huge consumption of concrete worldwide. There is therefore, a need for alternative materials suitable to replace sand in concrete. This study, looks into the possibility of using Itakpe Iron Ore Tailings (IIOT) to partially replace sand in concrete production. The IIOT was obtained from different locations at the tailings dump sites of National iron ore mining company in Itakpe, Kogi State, Nigeria. Sieve analysis, specific gravity, bulk density, moisture content, aggregate impact value and aggregate crushing value tests were carried out on the fine and coarse aggregate. Based on the British research establishment method, a normal weight concrete mix was designed with a target strength of 25 N/mm2. IIOT was used to replace sand at intervals of 5% ranging from 0% to 20%, resulting in one control sample and four others containing IIOT. Concrete cubes measuring 150 x 150 x 150mm were cast and their density and compressive strengths evaluated at 3, 7, 14, 21 and 28 days. The result of this study shows that all the concrete samples containing IIOT recorded higher density and compressive strength values than the control concrete sample. The concrete sample which contain 20 % tailings recorded the highest value of elastic modulus (19.6 GPa) this value is higher than that of the control sample by 17.4 %. The outcome of this study shows that, concrete mix produced according to this sample, can be used as eco-friendly material in the production of concrete. .