Assessment of Suitability of Nigerian Made Steel Bars for Structural Applications

Abstract

The mechanical properties of selected reinforcing steel bars produced from two rolling mills in Osun State, Nigeria were studied. An optical emission spectrometer was used for chemical composition analysis while the tensile test was carried out using a Universal Testing Machine. Izod v-notched was used for impact test, while the hardness values were obtained from Brinnel hardness tester. Scanning Electron Microscope was used for the fractured surface fractography. The Ultimate Tensile Strengths (UTS) of all the samples are higher than BSS4449:2005+A2:2005 standard and are also in close proximity to A707M-15 standard. Samples A12, B10 and B12 possessed higher yield strengths than samples A16 and B16 but lower than those of BSS4449:2005+A2:2005 and A707M-15 standards. Ductile property of the samples doubled the recommended Nst-65-Mn standard values while the hardness and ductility properties are higher than the recommended A707M-15 and BS4449 standards. The results showed that the investigated reinforcing bar samples possessed reasonably high strength and ductility when compared with available standards. Consequently, these bars would be suitable for structural applications where strength and ductility are critical properties. They would also be used in steel reinforcement applications that would require continuous and repetitive loading such as in buildings and bridges.