Review of Characteristic Strength Reports for Steel Reinforcement in Nigeria (2010-2021)

Abstract

There has been increasing concern in recent years over the structural integrity of construction in Nigeria. Reinforced concrete is the primary structural material in the country, so the strength of the steel reinforcement has become a major target for scrutiny. This study reviews the reported literature on reinforcing steel strengths from tests carried out in Nigeria between 2010-2021. The characteristic strength of steel is the basis for the design of steel reinforcement in both the Eurocode and British Standards used for design in Nigeria. However, it is noted that in every case, the characteristic strength results are missing or erroneously reported. A total of 18 studies are found, and the raw data for each study is analysed to derive the characteristic strength results. An average characteristic strength of 342.4 MPa is found from all the studies, lower than the 400 MPa and 500 MPa minimums assumed in the Eurocode and British Standards respectively. The finding here indicates that the widespread methodology around interpreting the tensile testing of steel reinforcement in Nigeria needs revisiting.