STRENGTH OF LOW STRENGTH CONCRETE

Fine aggregates used in concreting works posses different properties, thus affecting concrete quality and durability.. However, it was observed from previous literatures that these properties variation could adversely affect the performance of freshly mixed and hardened concrete, in terms of workability and strength. The aim of this study was to access the properties of fine aggregates sold at different locations in the Benin city by investigating their performance on concrete in both the fresh and hardened state. Concreting materials were procured from four different locations in Edo state namely; Okwae, Okun, Idugbo and Ovia areas of Edo state. Samples are to be labelled according to their locations. Experimental investigations were carried out to approved standards to produce fresh and hardened concrete. Slump and compressive tests was performed on all samples from the four different vendors at the end of 7, 14 and 28days respectively. Concrete prepared with constituents from the Okwae area, yielded favorable slump of 60.82mm and compressive strength of 13.72N/mm2 , thus proving its application in lightweight concreting works. However, concreting constituents from the Ovia area yielded slump value of 71mm and compressive strength of 11.92N/mm2 , proving its viability for use in plain concreting where strength is not the prevailing requirement. Concreting constituents from Idugbo and Okun yielded unfavorable values. The variations in the properties of concrete for all four vendors has no adverse effects on mix design calculations, only if the concrete would be used in light weight application. To ensure safety and economy in reinforced concrete construction, adequate quality control measures should be applied