FAILURE ANALYSIS OF STEEL REINFORCEMENT IN COLLAPSED BUILDING IN NIGERIA

Abstract

This research is based on worldwide concerns about the failure effect of mechanical properties in the reinforced steel bars gotten from building collapses in Nigeria. This work was investigated 12 collapsed building sites across Nigeria with the total number of 36 samples of reinforced steel bars 12 millimeter (mm) diameter being collected from the site in the cities of Lagos, Abuja, Jos, Uyo, Ibadan, Port Harcourt, Edo and Kano. For the strength of material analysis, each of the 12 samples of 12 mm diameter was considered for laboratory test. The results present the average values from each location of collapsed building and reveal that 100 % of reinforced steel from all collapsed building sites visited failed the standard tests. The significant factors from further demonstration to what the structural failure were also identified by analysis of microstructure and hardness techniques through the means of scanning electron microscope (SEM) and energy dispersive x-ray spectroscopy (EDS). Both predicted the presence of high weight percent (wt. %) concentration of carbon (0.51 %), phosphorus (0.71 %), sulphur (0.86 %) and oxygen (6.48 %) which proved brittle nature of the steel. Conclusively, the implication of the findings from this thesis confirms the failed steel reinforcement as one of the major contributions to building collapses.