Verification of Properties of Concrete Reinforcement Bars: Nigeria as a Case Study

An investigation was conducted into the level of conformance of ribbed steel bars used in Nigeria's structural concrete practice to relevant international and local provisions. In this research, all bars imported into Nigeria from member countries of ISO as well as those marked with the identity of the local producing mill are classified as steel of recognizable origin while bars imported from ISO nonmember countries as well as those without an identifying mark from the producing works are classified as steel of non recognizable origin. The investigation showed that steel of recognizable origin satisfied both local and ISO requirements for strength and ductility whereas those bars of nonrecognizable origin failed to satisfy the above requirements for high-yield bars but satisfied the local specifications if used as mild steel. Based on these findings, appropriate recommendations are made.